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172-415: WinFS includes a relational database for storage of information, and allows any type of information to be stored in it, provided there is a well defined schema for the type. Individual data items could then be related together by relationships, which are either inferred by the system based on certain attributes or explicitly stated by the user. As the data has a well defined schema, any application can reuse

344-555: A WinFS store as a specialization of the Item type. By default, WinFS provides Item types for Files, Contact, Documents, Pictures, Audio, Video, Calendar, and Messages. The File Item can store any generic data, which is stored in file systems as files. But unless an advanced schema is provided for the file, by defining it to be a specialized Item, WinFS will not be able to access its data. Such a file Item can only support being related to other Items. A developer can extend any of these types, or

516-569: A data model which has both the semantics as well as relationships of data defined. WinFS aims to provide such a data model and the runtime infrastructure that can be used to store the data, as well as the relationships between data items according to the data model, doing so at a satisfactory level of performance. WinFS natively recognizes different types of data, such as picture , e-mail , document , audio , video , calendar , contact , rather than just leaving them as raw unanalyzed bytestreams (as most file systems do). Data stored and managed by

688-493: A different context. For example, the reference of the word here depends on the location in which it is used. A closely related approach is possible world semantics, which allows expressions to refer not only to entities in the actual world but also to entities in other possible worlds. According to this view, expressions like the first man to run a four-minute mile refer to different persons in different worlds. This view can also be used to analyze sentences that talk about what

860-440: A different sense have the same referent. For instance, the sentence "the morning star is the evening star" is informative and people can learn something from it. The sentence "the morning star is the morning star", by contrast, is an uninformative tautology since the expressions are identical not only on the level of reference but also on the level of sense. Compositionality is a key aspect of how languages construct meaning. It

1032-498: A different set of data. So when a search is made that encompasses multiple relations, the different sets of data are retrieved individually and a union of the different sets is computed. The resulting set contains only those data items that correspond to all the relations. WinFS includes better support for handling data that changes frequently. Using WinFS Notifications , applications choose to be notified of changes to selected data Items . WinFS will raise an ItemChangedEvent , using

1204-459: A document and a contact can be related by an Authored By relationship. Relationships are also exposed as properties; for example if a document is related to a contact by a Created By relationship, then the document will have a Created By property. When it is accessed, the relationship is traversed and the related data returned. By following the relations, all related data can be reached. WinFS promotes sharing of data between applications by making

1376-477: A downloadable update after Vista's release. On August 29, 2005, Microsoft quietly made Beta 1 of WinFS available to MSDN subscribers. It worked on Windows XP , and required the .NET Framework to run. The WinFS API was included in the System.Storage namespace. The beta was refreshed on December 1, 2005 to be compatible with version 2.0 of the .NET Framework. WinFS Beta 2 was planned for some time later in 2006, and

1548-420: A folder hierarchy, such as finding "pictures which have person X" . The attributes can be recognizable by either the file system natively, or via some extension. Desktop search applications take this concept a step further. They extract data, including attributes, from files and index it. To extract the data, they use a filter for each file format. This allows for searching based on both the file's attributes and

1720-435: A list of all items present in the store and present them in a folder view. The shell object also allows searching information in the datastore. A data unit that has to be stored in a WinFS store is called a WinFS Item . A WinFS item, along with the core data item, also contains information on how the data item is related to other data. This Relationship is stored in terms of logical links. Links specify which other data items

1892-541: A lower integrity process. The primary mode of data retrieval from a WinFS store is querying the WinFS store according to some criteria, which returns an enumerable set of items matching the criteria. The criteria for the query is specified using the OPath query language . The returned data are made available as instances of the type schemas, conforming to the .NET object model . The data in them can be accessed by accessing

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2064-413: A more complex meaning structure. In the expression "Beethoven likes Schubert", the verb like connects a liker to the object of their liking. Other sentence parts modify meaning rather than form new connections. For instance, the adjective red modifies the color of another entity in the expression red car . A further compositional device is variable binding, which is used to determine the reference of

2236-454: A network of relationships, which is called a many-to-many relationship. Creating a relationship between two Items creates another field in the data of the Items concerned which refer the row in the other Item's table where the related object is stored. In WinFS, a Relationship is an instance of the base type Relationship, which is extended to signify a specialization of a relation. A Relationship

2408-399: A new row is written to the table, a new unique value for the primary key is generated; this is the key that the system uses primarily for accessing the table. System performance is optimized for PKs. Other, more natural keys may also be identified and defined as alternate keys (AK). Often several columns are needed to form an AK (this is one reason why a single integer column is usually made

2580-503: A new rule that consists of the condition and action of the parent rule plus something more. WinFS supports creating Rich Application Views (RAV) by aggregating different data in a virtual table format. Unlike database view , where each individual element can only be a scalar value, RAVs can have complex Items or even collections of Items. The actual data can be across multiple data types or instances and can even be retrieved by traversing relationships. RAVs are intrinsically paged (dividing

2752-414: A particular language. Some semanticists also include the study of lexical units other than words in the field of lexical semantics. Compound expressions like being under the weather have a non-literal meaning that acts as a unit and is not a direct function of its parts. Another topic concerns the meaning of morphemes that make up words, for instance, how negative prefixes like in- and dis- affect

2924-413: A particular language. The same symbol may refer to one object in one language, to another object in a different language, and to no object in another language. Many other concepts are used to describe semantic phenomena. The semantic role of an expression is the function it fulfills in a sentence. In the sentence "the boy kicked the ball", the boy has the role of the agent who performs an action. The ball

3096-413: A per-application basis, in situations where an application wants to store its data in WinFS, but not share the structure of that data with other applications, or they can be made available across the system. The most important difference between a file system and WinFS is that WinFS knows the type of each data item that it stores. And the type specifies the properties of the data item. The WinFS type system

3268-733: A previous query, was later incorporated in Windows Vista. Examples of uses of the technology are the object-relational mapping components into ADO.NET Entity Framework ; support for unstructured data, adminless mode of operation, support for file system objects via the FILESTREAM data type, and hierarchical data in SQL Server 2008 , then codenamed Katmai , as well as integration with Win32 APIs and Windows Shell and support for traversal of hierarchies by traversing relationships into later releases of Microsoft SQL Server ; and

3440-434: A pseudo-type called Folder, which is present only to participate in holding relationships and emulate file/folder organization. Since any WinFS Item can be related with more than one Folder item, from an end user perspective, an item can reside in multiple folders without duplicating the actual data. Applications can also analyze the relationship graphs to present various filters. For example, an email application can analyze

3612-445: A relational database system is composed of Codd's 12 rules . However, no commercial implementations of the relational model conform to all of Codd's rules, so the term has gradually come to describe a broader class of database systems, which at a minimum: In 1974, IBM began developing System R , a research project to develop a prototype RDBMS. The first system sold as an RDBMS was Multics Relational Data Store (June 1976). Oracle

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3784-455: A single relation, even though they may grab information from several relations. Also, derived relations can be used as an abstraction layer . A domain describes the set of possible values for a given attribute, and can be considered a constraint on the value of the attribute. Mathematically, attaching a domain to an attribute means that any value for the attribute must be an element of the specified set. The character string "ABC" , for instance,

3956-445: A speaker remains silent on a certain topic. A closely related distinction by the semiotician Charles W. Morris holds that semantics studies the relation between words and the world, pragmatics examines the relation between words and users, and syntax focuses on the relation between different words. Semantics is related to etymology , which studies how words and their meanings changed in the course of history. Another connected field

4128-438: A strict distinction between meaning and syntax and by relying on various formal devices to explore the relation between meaning and cognition. Computational semantics examines how the meaning of natural language expressions can be represented and processed on computers. It often relies on the insights of formal semantics and applies them to problems that can be computationally solved. Some of its key problems include computing

4300-459: A strong sense, the principle of compositionality states that the meaning of a complex expression is not just affected by its parts and how they are combined but fully determined this way. It is controversial whether this claim is correct or whether additional aspects influence meaning. For example, context may affect the meaning of expressions; idioms like " kick the bucket " carry figurative or non-literal meanings that are not directly reducible to

4472-558: A system. For increased security, the system design may grant access to only the stored procedures and not directly to the tables. Fundamental stored procedures contain the logic needed to insert new and update existing data. More complex procedures may be written to implement additional rules and logic related to processing or selecting the data. The relational database was first defined in June 1970 by Edgar Codd , of IBM's San Jose Research Laboratory . Codd's view of what qualifies as an RDBMS

4644-508: A term. For example, the last part of the expression "the woman who likes Beethoven" specifies which woman is meant. Parse trees can be used to show the underlying hierarchy employed to combine the different parts. Various grammatical devices, like the gerund form, also contribute to meaning and are studied by grammatical semantics. Formal semantics uses formal tools from logic and mathematics to analyze meaning in natural languages. It aims to develop precise logical formalisms to clarify

4816-407: A text that come before and after it. Context affects the meaning of various expressions, like the deictic expression here and the anaphoric expression she . A syntactic environment is extensional or transparent if it is always possible to exchange expressions with the same reference without affecting the truth value of the sentence. For example, the environment of the sentence "the number 8

4988-460: A traditional file system can retrieve and search data based only on the filename, because the only knowledge it has about the data is the name of the files that store the data. A better solution is to tag files with attributes that describe them. Attributes are metadata about the files such as the type of file (such as document , picture , music , creator , etc.). This allows files to be searched for by their attributes, in ways not possible using

5160-414: A tuple (restricting combinations of attributes) or to an entire relation. Since every attribute has an associated domain, there are constraints ( domain constraints ). The two principal rules for the relational model are known as entity integrity and referential integrity . Every relation /table has a primary key, this being a consequence of a relation being a set . A primary key uniquely specifies

5332-476: A tuple within a table. While natural attributes (attributes used to describe the data being entered) are sometimes good primary keys, surrogate keys are often used instead. A surrogate key is an artificial attribute assigned to an object which uniquely identifies it (for instance, in a table of information about students at a school they might all be assigned a student ID in order to differentiate them). The surrogate key has no intrinsic (inherent) meaning, but rather

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5504-420: A type, the type of item stored defines its properties. The properties of an Item may be a ScalarType, which defines the smallest unit of information a property can have, or a NestedType, which is a collection of more than one ScalarTypes and/or NestedTypes. All WinFS types are made available as .NET CLR classes . Any object represented as a data unit, such as contact, image, video, document etc., can be stored in

5676-424: A uniform interface providing access to the data stored in the fields. Thus any application can retrieve object of any Item type and can use the data in the object, without being aware of the physical structure the data was stored in. WinFS types are exposed as .NET classes, which can be instantiated as .NET objects. Data are stored in these type instances by setting their properties. Once done, they are persisted into

5848-457: A uniform signifying rank , and the presence of vultures indicating a nearby animal carcass. Semantics further contrasts with pragmatics , which is interested in how people use language in communication. An expression like "That's what I'm talking about" can mean many things depending on who says it and in what situation. Semantics is interested in the possible meanings of expressions: what they can and cannot mean in general. In this regard, it

6020-416: A video presentation, named IWish, showing mockup interfaces that showed how applications would expose interfaces that take advantage of a unified type system. The concepts shown in the video ranged from applications using the relationships of items to dynamically offer filtering options to applications grouping multiple related data types and rendering them in a unified presentation. WinFS was billed as one of

6192-427: A word means by looking at its letters and one needs to consult a dictionary instead. Compositionality is often used to explain how people can formulate and understand an almost infinite number of meanings even though the amount of words and cognitive resources is finite. Many sentences that people read are sentences that they have never seen before and they are nonetheless able to understand them. When interpreted in

6364-484: Is hermeneutics , which is the art or science of interpretation and is concerned with the right methodology of interpreting text in general and scripture in particular. Metasemantics examines the metaphysical foundations of meaning and aims to explain where it comes from or how it arises. The word semantics originated from the Ancient Greek adjective semantikos , meaning 'relating to signs', which

6536-400: Is 8. Semanticists commonly distinguish the language they study, called object language, from the language they use to express their findings, called metalanguage . When a professor uses Japanese to teach their student how to interpret the language of first-order logic then the language of first-order logic is the object language and Japanese is the metalanguage. The same language may occupy

6708-521: Is a relational database management system ( RDBMS ). Many relational database systems are equipped with the option of using SQL (Structured Query Language) for querying and updating the database. The concept of relational database was defined by E. F. Codd at IBM in 1970. Codd introduced the term relational in his research paper "A Relational Model of Data for Large Shared Data Banks". In this paper and later papers, he defined what he meant by relation . One well-known definition of what constitutes

6880-529: Is a derivative of sēmeion , the noun for ' sign '. It was initially used for medical symptoms and only later acquired its wider meaning regarding any type of sign, including linguistic signs. The word semantics entered the English language from the French term semantique , which the linguist Michel Bréal first introduced at the end of the 19th century. Semantics studies meaning in language, which

7052-442: Is a mapping between two items, a Source and a Target. The source has an Outgoing Relationship, whereas the target gets an Incoming Relationship. WinFS provides three types of primitive relationships – Holding Relationship , Reference Relationship and Embedding Relationship . Any custom relationship between two data types are instances of these relationship types. Relationships between two Items can either be set programmatically by

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7224-478: Is a valid query string. These operators can be used to execute complex searches such as The above code snippet creates an ItemSearcher object that searches on the OutContactRelationship instance that relates pictures and contacts, in effect searching all pictures related with a contact. It then runs the query Name LIKE 'A*'" on all contacts reachable through OutContactRelationship , returning

7396-503: Is analogous to using the index of a book to go directly to the page on which the information you are looking for is found, so that you do not have to read the entire book to find what you are looking for. Relational databases typically supply multiple indexing techniques, each of which is optimal for some combination of data distribution, relation size, and typical access pattern. Indices are usually implemented via B+ trees , R-trees , and bitmaps . Indices are usually not considered part of

7568-577: Is and how it arises. It investigates how expressions are built up from different layers of constituents, like morphemes , words , clauses , sentences , and texts , and how the meanings of the constituents affect one another. Semantics can focus on a specific language, like English, but in its widest sense, it investigates meaning structures relevant to all languages. As a descriptive discipline, it aims to determine how meaning works without prescribing what meaning people should associate with particular expressions. Some of its key questions are "How do

7740-430: Is closely associated with the .NET framework's concept of classes and inheritance . A new type can be created by extending and nesting any predefined types. WinFS provides four predefined base types – Items , Relationships , ScalarTypes and NestedTypes . An Item is the fundamental data object which can be stored, and a Relationship is the relation or link between two data items. Since all WinFS items must have

7912-426: Is created through the combination of expressions belonging to different syntactic categories. Dynamic semantics is a subfield of formal semantics that focuses on how information grows over time. According to it, "meaning is context change potential": the meaning of a sentence is not given by the information it contains but by the information change it brings about relative to a context. Cognitive semantics studies

8084-591: Is created which contains field "Name" and if the value of that field is some particular name, a relationship should be created that relates the Item with some other Item. WinFS rules can also access any external application. For example, a rule can be built which launches a Notify application whenever a mail is received from a particular contact. WinFS rules can also be used to add new properties fields to existing data Items. WinFS rules are also exposed as .NET CLR objects. As such any rule can be used for any purpose. A rule can even be extended by inheriting from it to form

8256-445: Is described but an experience takes place, like when a girl sees a bird. In this case, the girl has the role of the experiencer. Other common semantic roles are location, source, goal, beneficiary, and stimulus. Lexical relations describe how words stand to one another. Two words are synonyms if they share the same or a very similar meaning, like car and automobile or buy and purchase . Antonyms have opposite meanings, such as

8428-408: Is even" is extensional because replacing the expression the number 8 with the number of planets in the solar system does not change its truth value. For intensional or opaque contexts , this type of substitution is not always possible. For instance, the embedded clause in "Paco believes that the number 8 is even" is intensional since Paco may not know that the number of planets in the solar system

8600-514: Is interested in how meanings evolve and change because of cultural phenomena associated with politics , religion, and customs . For example, address practices encode cultural values and social hierarchies, as in the difference of politeness of expressions like tu and usted in Spanish or du and Sie in German in contrast to English, which lacks these distinctions and uses

8772-454: Is limited to the meaning of linguistic expressions. It concerns how signs are interpreted and what information they contain. An example is the meaning of words provided in dictionary definitions by giving synonymous expressions or paraphrases, like defining the meaning of the term ram as adult male sheep . There are many forms of non-linguistic meaning that are not examined by semantics. Actions and policies can have meaning in relation to

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8944-497: Is not in the integer domain, but the integer value 123 is. Another example of domain describes the possible values for the field "CoinFace" as ("Heads","Tails"). So, the field "CoinFace" will not accept input values like (0,1) or (H,T). Constraints are often used to make it possible to further restrict the domain of an attribute. For instance, a constraint can restrict a given integer attribute to values between 1 and 10. Constraints provide one method of implementing business rules in

9116-446: Is possible or what is necessary: possibility is what is true in some possible worlds while necessity is what is true in all possible worlds. Ideational theories, also called mentalist theories, are not primarily interested in the reference of expressions and instead explain meaning in terms of the mental states of language users. One historically influential approach articulated by John Locke holds that expressions stand for ideas in

9288-430: Is sometimes defined as the study of context-independent meaning. Pragmatics examines which of these possible meanings is relevant in a particular case. In contrast to semantics, it is interested in actual performance rather than in the general linguistic competence underlying this performance. This includes the topic of additional meaning that can be inferred even though it is not literally expressed, like what it means if

9460-444: Is sometimes divided into two complementary approaches: semasiology and onomasiology . Semasiology starts from words and examines what their meaning is. It is interested in whether words have one or several meanings and how those meanings are related to one another. Instead of going from word to meaning, onomasiology goes from meaning to word. It starts with a concept and examines what names this concept has or how it can be expressed in

9632-504: Is sometimes understood as a mental phenomenon that helps people identify the objects to which an expression refers. Some semanticists focus primarily on sense or primarily on reference in their analysis of meaning. To grasp the full meaning of an expression, it is usually necessary to understand both to what entities in the world it refers and how it describes them. The distinction between sense and reference can explain identity statements , which can be used to show how two expressions with

9804-453: Is summarized in Codd's 12 rules . A relational database has become the predominant type of database. Other models besides the relational model include the hierarchical database model and the network model . The table below summarizes some of the most important relational database terms and the corresponding SQL term: In a relational database, a relation is a set of tuples that have

9976-413: Is the branch of semantics that studies word meaning . It examines whether words have one or several meanings and in what lexical relations they stand to one another. Phrasal semantics studies the meaning of sentences by exploring the phenomenon of compositionality or how new meanings can be created by arranging words. Formal semantics relies on logic and mathematics to provide precise frameworks of

10148-416: Is the idea that the meaning of a complex expression is a function of the meanings of its parts. It is possible to understand the meaning of the sentence "Zuzana owns a dog" by understanding what the words Zuzana , owns , a and dog mean and how they are combined. In this regard, the meaning of complex expressions like sentences is different from word meaning since it is normally not possible to deduce what

10320-419: Is the object to which the expression points. The sense of an expression is the way in which it refers to that object or how the object is interpreted. For example, the expressions morning star and evening star refer to the same planet, just like the expressions 2 + 2 and 3 + 1 refer to the same number. The meanings of these expressions differ not on the level of reference but on the level of sense. Sense

10492-404: Is the theme or patient of this action as something that does not act itself but is involved in or affected by the action. The same entity can be both agent and patient, like when someone cuts themselves. An entity has the semantic role of an instrument if it is used to perform the action, for instance, when cutting something with a knife then the knife is the instrument. For some sentences, no action

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10664-404: Is true. Many related disciplines investigate language and meaning. Semantics contrasts with other subfields of linguistics focused on distinct aspects of language. Phonology studies the different types of sounds used in languages and how sounds are connected to form words while syntax examines the rules that dictate how to arrange words to create sentences. These divisions are reflected in

10836-450: Is used if the different meanings are closely related to one another, like the meanings of the word head , which can refer to the topmost part of the human body or the top-ranking person in an organization. The meaning of words can often be subdivided into meaning components called semantic features . The word horse has the semantic feature animate but lacks the semantic feature human . It may not always be possible to fully reconstruct

11008-446: Is useful through its ability to uniquely identify a tuple. Another common occurrence, especially in regard to N:M cardinality is the composite key . A composite key is a key made up of two or more attributes within a table that (together) uniquely identify a record. Foreign key refers to a field in a relational table that matches the primary key column of another table. It relates the two keys. Foreign keys need not have unique values in

11180-677: The NTFS filesystem which is used in modern versions of Microsoft Windows, store files and other objects only as a stream of bytes , and have little or no information about the data stored in the files. Such file systems also provide only a single way of organizing the files, namely via directories and file names. Because a file system has no knowledge about the data it stores, applications tend to use their own, often proprietary , file formats . This hampers sharing of data between multiple applications. It becomes difficult to create an application which processes information from multiple file types, because

11352-545: The Windows authentication system to provide two data protection mechanisms. First, there is share-level security that controls access to your WinFS share. Second, there is item level security that supports NT compatible security descriptors. The process accessing the item must have enough privileges to access it. Also in Vista there is the concept of "integrity level" for an application. Higher integrity data cannot be accessed by

11524-399: The name property of a contact are same, then WinFS can relate the contact with the picture. Relations can also be specified by other applications or the user. WinFS provides unified storage, but stops short of defining the format that is to be stored in the data stores. Instead it supports writing data in application-specific formats. But applications must provide a schema that defines how

11696-417: The normal forms . Connolly and Begg define database management system (DBMS) as a "software system that enables users to define, create, maintain and control access to the database". RDBMS is an extension of that initialism that is sometimes used when the underlying database is relational. An alternative definition for a relational database management system is a database management system (DBMS) based on

11868-569: The relational model . Most databases in widespread use today are based on this model. RDBMSs have been a common option for the storage of information in databases used for financial records, manufacturing and logistical information, personnel data, and other applications since the 1980s. Relational databases have often replaced legacy hierarchical databases and network databases , because RDBMS were easier to implement and administer. Nonetheless, relational stored data received continued, unsuccessful challenges by object database management systems in

12040-609: The subject relationship of all the photos to find the contact items. Similarly, it can filter all emails in last month and access the communicated with relation to reach the contacts. The common contacts can then be figured out from the two sets of results and their phone number retrieved by accessing the suitable property of the contact items. In addition to fully schematized data (like XML and relational data), WinFS supports semi-structured data (such as images, which have an unstructured bitstream plus structured metadata) as well as unstructured data (such as files) as well. It stores

12212-399: The use theory , and inferentialist semantics . The study of semantic phenomena began during antiquity but was not recognized as an independent field of inquiry until the 19th century. Semantics is relevant to the fields of formal logic, computer science , and psychology . Semantics is the study of meaning in languages . It is a systematic inquiry that examines what linguistic meaning

12384-598: The vocabulary as a whole. This includes the study of lexical relations between words, such as whether two terms are synonyms or antonyms. Lexical semantics categorizes words based on semantic features they share and groups them into semantic fields unified by a common subject. This information is used to create taxonomies to organize lexical knowledge, for example, by distinguishing between physical and abstract entities and subdividing physical entities into stuff and individuated entities . Further topics of interest are polysemy, ambiguity, and vagueness . Lexical semantics

12556-484: The .NET Event model, when a subscribed-to Item changes, and the event will be published to the applications. WinFS includes an Information Agent feature for the management, retrieval, and storage of end-user notification rules and preferences for changes to items in the data store. Using Information Agent, it is possible to automatically define relations to new items based on events such as appointments, with an example being that appointments can be related to photos based on

12728-496: The 1980s and 1990s, (which were introduced in an attempt to address the so-called object–relational impedance mismatch between relational databases and object-oriented application programs), as well as by XML database management systems in the 1990s. However, due to the expanse of technologies, such as horizontal scaling of computer clusters , NoSQL databases have recently become popular as an alternative to RDBMS databases. Distributed Relational Database Architecture (DRDA)

12900-579: The Business Events folder ") or more complex possibilities. Information Agent can also forward notifications to other devices (" if I receive a high priority email from my boss, send a notification to my phone ") and is similar to Rules and Alerts functionality of Microsoft Outlook. Relational database A relational database ( RDB ) is a database based on the relational model of data, as proposed by E. F. Codd in 1970. A database management system used to maintain relational databases

13072-500: The Contact, by populating the properties field and storing it. Only those fields marked as mandatory needs to be filled up during initial save. Other fields may be populated later by the user, or not populated at all. If more properties fields, such as last conversed date , need to be added, this type can be extended to accommodate them. Item types for other data can be defined similarly. WinFS creates tables for all defined Items. All

13244-448: The PK). Both PKs and AKs have the ability to uniquely identify a row within a table. Additional technology may be applied to ensure a unique ID across the world, a globally unique identifier , when there are broader system requirements. The primary keys within a database are used to define the relationships among the tables. When a PK migrates to another table, it becomes a foreign key (FK) in

13416-571: The WinFS runtime uses to implement the functionality. The WinFS runtime exposes services such as Synchronization and Rules that can be used to synchronize WinFS stores or perform certain actions on the occurrence of certain events. WinFS runs as a service that runs three processes : It allows programmatic access to its features via a set of .NET Framework APIs . These enable applications to define custom-made data types, define relationships among data, store and retrieve information, and allow advanced searches. The applications can then aggregate

13588-429: The WinFS store. A WinFS store is accessed using an ItemContext class (see Data retrieval section for details). ItemContext allows transactional access to the WinFS store; i.e. all the operations since binding an ItemContext object to a store till it is closed either all succeed or are all rolled back. As changes are made to the data, they are not written to the disc; rather they are written to an in-memory log. Only when

13760-443: The access-restricted folder named "System Volume Information" (placed in the volume root), in folders under the folder "WinFS" with names of GUIDs of these stores. At the bottom of the WinFS stack lies WinFS Core , which interacts with the filesystem and provides file-access and -addressing capabilities. The relational engine leverages the WinFS core services to present a structured store and other services such as locking , which

13932-515: The application creating the data, or the user can use the WinFS Item Browser to manually relate the Items. A WinFS item browser can also graphically display the items and how they are related, to enable the user to know how their data are organized. WinFS includes Rules , which are executed when a certain condition is met. WinFS rules work on data and data relationships. For example, a rule can be created that states that whenever an Item

14104-415: The base type Item, to provide a type for their custom data. The data contained in an Item is defined in terms of properties, or fields that hold the actual data. For example, an Item Contact may have a field Name that is a ScalarType, and one field Address , a NestedType, which is further composed of two ScalarTypes. To define this type, the base class Item is extended and the necessary fields are added to

14276-438: The basis of interaction among these tables. These relationships can be modelled as an entity-relationship model . In order for a database management system (DBMS) to operate efficiently and accurately, it must use ACID transactions . Part of the programming within a RDBMS is accomplished using stored procedures (SPs). Often procedures can be used to greatly reduce the amount of information transferred within and outside of

14448-735: The class. A NestedType field can be defined as another class that contains the two ScalarType fields. Once the type is defined, a schema has to be defined, which denotes the primitive type of each field, for example, the Name field is a String, the Address field is a custom defined Address class, both the fields of which are Strings. Other primitive types that WinFS supports are Integer , Byte , Decimal , Float , Double , Boolean and DateTime, among others. The schema will also define which fields are mandatory and which are optional. The Contact Item defined in this way will be used to store information regarding

14620-420: The cognitive conceptual structures of humans are universal or relative to their linguistic background. Another research topic concerns the psychological processes involved in the application of grammar. Other investigated phenomena include categorization, which is understood as a cognitive heuristic to avoid information overload by regarding different entities in the same way, and embodiment , which concerns how

14792-402: The columns represent values attributed to that instance (such as address or price). For example, each row of a class table corresponds to a class, and a class corresponds to multiple students, so the relationship between the class table and the student table is "one to many" Each row in a table has its own unique key. Rows in a table can be linked to rows in other tables by adding a column for

14964-454: The conditions under which it would be true. This can happen even if one does not know whether the conditions are fulfilled. The semiotic triangle , also called the triangle of meaning, is a model used to explain the relation between language, language users, and the world, represented in the model as Symbol , Thought or Reference , and Referent . The symbol is a linguistic signifier , either in its spoken or written form. The central idea of

15136-488: The connection is closed are the changes written to the disc in a batch. This helps to optimize disc I/O. The following code snippet, written in C# , creates a contact and stores it in a WinFS store. A datum can be related to one more item, giving rise to a one-to-one relationship, or with more than one items, resulting in a one-to-many relationship. The related items, in turn, may be related to other data items as well, resulting in

15308-408: The context, like the deictic terms here and I . To avoid these problems, referential theories often introduce additional devices. Some identify meaning not directly with objects but with functions that point to objects. This additional level has the advantage of taking the context of an expression into account since the same expression may point to one object in one context and to another object in

15480-478: The contrast between alive and dead or fast and slow . One term is a hyponym of another term if the meaning of the first term is included in the meaning of the second term. For example, ant is a hyponym of insect . A prototype is a hyponym that has characteristic features of the type it belongs to. A robin is a prototype of a bird but a penguin is not. Two words with the same pronunciation are homophones like flour and flower , while two words with

15652-399: The corresponding physical object. The relation is only established indirectly through the mind of the language user. When they see the symbol, it evokes a mental image or a concept, which establishes the connection to the physical object. This process is only possible if the language user learned the meaning of the symbol before. The meaning of a specific symbol is governed by the conventions of

15824-428: The current item is related with. Put in other words, links specify the relationship of the data with other data items. Links are physically stored using a link identifier, which specifies the name and intent of the relationship, such as type of or consists of . The link identifier is stored as an attribute of the data item. All the objects that have the same link ID are considered to be related. An XML schema , defining

15996-617: The current understanding on the relational model, as expressed by Christopher J. Date , Hugh Darwen and others), it is not relational. This view, shared by many theorists and other strict adherents to Codd's principles, would disqualify most DBMSs as not relational. For clarification, they often refer to some RDBMSs as truly-relational database management systems (TRDBMS), naming others pseudo-relational database management systems (PRDBMS). As of 2009, most commercial relational DBMSs employ SQL as their query language . Alternative query languages have been proposed and implemented, notably

16168-400: The data and present the aggregated data to the user. WinFS stores data in relational stores, which are exposed as virtual locations called stores . A WinFS store is a common repository where any application can store data along with its metadata, relationships and schema. WinFS runtime can apply certain relationships itself; for example, if the values of the subject property of a picture and

16340-465: The data in it. However, this still does not help in managing related data, as disparate items do not have any relationships defined. For example, it is impossible to search for "the phone numbers of all persons who live in Acapulco and each have more than 100 appearances in my photo collection and from whom I have had e-mail within the last month" . Such a search could not be done unless it is based on

16512-553: The data item can be made available to any application that requests it. This is done by the use of schemas. For every type of data item that is to be stored in WinFS, a corresponding schema needs to be provided to define the type, structure and associations of the data. These schemas are defined using XML . Predefined WinFS schemas include schemas for documents, e-mail, appointments, tasks, media, audio, video, and also includes system schemas that include configuration, programs, and other system-related data. Custom schemas can be defined on

16684-445: The data store to update the data. The ItemContext object is closed (which marks the end of association of the object with the store) when the queries are made or changes merged into the store. Related items can also be accessed through the items. The IncomingRelationships and OutgoingRelationships properties give access to all the set of relationship instances, typed to the name of the relationship. These relationship objects expose

16856-436: The data types accessible to all applications, along with their schemas. When an application wants to use a WinFS type, it can use the schema to find the data structure and can use the information. So, an application has access to all data on the system even though the developer did not have to write parsers to recognize the different data formats. It can also use relationships and related data to create dynamic filters to present

17028-430: The data; and using the relationships, related data can be effectively organized as well as retrieved. Because the system knows the structure and intent of the information, it can be used to make complex queries that enable advanced searching through the data and aggregating various data items by exploiting the relationships between them. While WinFS and its shared type schema make it possible for an application to recognize

17200-401: The database and support subsequent data use within the application layer. SQL implements constraint functionality in the form of check constraints . Constraints restrict the data that can be stored in relations . These are usually defined using expressions that result in a Boolean value, indicating whether or not the data satisfies the constraint. Constraints can apply to single attributes, to

17372-469: The database, as they are considered an implementation detail, though indices are usually maintained by the same group that maintains the other parts of the database. The use of efficient indexes on both primary and foreign keys can dramatically improve query performance. This is because B-tree indexes result in query times proportional to log(n) where n is the number of rows in a table and hash indexes result in constant time queries (no size dependency as long as

17544-401: The dates the photos were taken, enabling queries for birthdays or holidays without needing to know the actual dates of such events (" find all photos taken on this birthday "). Other examples include automatically moving new items to specific folders based on a rule as determined by appointment times and dates the photos were taken (" when I import a photo taken during a business event, move it to

17716-447: The different data types, the application still has to be coded to render the different data types. Consequently, it would not allow development of a single application that can view or edit all data types; rather, what WinFS enables applications to do is understand the structure of all data and extract the information that they can use further. When WinFS was introduced at the 2003 Professional Developers Conference , Microsoft also released

17888-425: The different stores when the data change are removed. Thus WinFS can reduce redundancies. Access to all the data in the system allows complex searches for data across all the data items managed by WinFS. In the example used above ( "the phone numbers of all persons who live in Acapulco and each have more than 100 appearances in my photo collection and with whom I have had e-mail within last month" ), WinFS can traverse

18060-399: The distinction between sense and reference . Sense is given by the ideas and concepts associated with an expression while reference is the object to which an expression points. Semantics contrasts with syntax , which studies the rules that dictate how to create grammatically correct sentences, and pragmatics , which investigates how people use language in communication. Lexical semantics

18232-488: The entire set of data into smaller pages containing disconnected subsets of the data) by the WinFS runtime. The page size is defined during creation of the view and the WinFS API exposes methods to iterate over the pages. RAVs also supports modification of the view according to different grouping parameters. Views can also be queried against. Even though all data are shared, everything is not equally accessible. WinFS uses

18404-541: The fact that it is possible to master some aspects of a language while lacking others, like when a person knows how to pronounce a word without knowing its meaning. As a subfield of semiotics, semantics has a more narrow focus on meaning in language while semiotics studies both linguistic and non-linguistic signs. Semiotics investigates additional topics like the meaning of non-verbal communication , conventional symbols , and natural signs independent of human interaction. Examples include nodding to signal agreement, stripes on

18576-471: The fields defined for the Item form the columns of the table and all instances of the Item are stored as rows in the table for the respective Items. Whenever some field in the table refers to data in some other table, it is considered a relationship. The schema of the relationship specifies which tables are involved and what the kind and name of the relationship is. The WinFS runtime manages the relationship schemas. All Items are exposed as .NET CLR objects , with

18748-726: The file format should be interpreted. For example, a schema could be added to allow WinFS to understand how to read and thus be able to search and analyze, (say) a PDF file. By using the schema, any application can read data from any other application, and this also allows different applications to write in each other's format by sharing the schema. Multiple WinFS stores can be created on a single machine. This allows different classes of data to be kept segregated; for example, official documents and personal documents can be kept in different stores. WinFS, by default, provides only one store, named "DefaultStore". WinFS stores are exposed as shell objects, akin to Virtual folders , which dynamically generate

18920-422: The five leading proprietary software relational database vendors by revenue were Oracle (48.8%), IBM (20.2%), Microsoft (17.0%), SAP including Sybase (4.6%), and Teradata (3.7%). Semantics Semantics is the study of linguistic meaning . It examines what meaning is, how words get their meaning, and how the meaning of a complex expression depends on its parts. Part of this process involves

19092-423: The foreground while the base is the background that provides the context of this aspect without being at the center of attention. For example, the profile of the word hypotenuse is a straight line while the base is a right-angled triangle of which the hypotenuse forms a part. Cognitive semantics further compares the conceptual patterns and linguistic typologies across languages and considers to what extent

19264-408: The goal they serve. Fields like religion and spirituality are interested in the meaning of life , which is about finding a purpose in life or the significance of existence in general. Linguistic meaning can be analyzed on different levels. Word meaning is studied by lexical semantics and investigates the denotation of individual words. It is often related to concepts of entities, like how

19436-440: The hierarchical organization as used in file-systems. In a file system, each file or folder is contained in only one folder. But WinFS Items can participate in any number of holding relationships, that too with any other items. As such, end users are not limited to only file/folder organization. Rather, a contact can become a container for documents; a picture a container for contacts and so on. For legacy compatibility, WinFS includes

19608-425: The information the application deals with. The WinFS API further abstracts the task of accessing data. All WinFS types are exposed as .NET objects with the properties of the object directly mapping to the properties of the data type. Also, by letting different applications that deal with the same data share the same WinFS data instance rather than storing the same data in different files, the hassles of synchronizing

19780-431: The information. Indexing speeds up joins significantly, and traversing relationships to retrieve related data is performed very fast. Indexes are also used during information search; searching and querying use the indexes to quickly complete the operations, much like desktop search systems. The development of WinFS is an extension to a feature that was initially planned in the early 1990s. Dubbed Object File System , it

19952-453: The language user's bodily experience affects the meaning of expressions. Frame semantics is an important subfield of cognitive semantics. Its central idea is that the meaning of terms cannot be understood in isolation from each other but needs to be analyzed on the background of the conceptual structures they depend on. These structures are made explicit in terms of semantic frames. For example, words like bride, groom, and honeymoon evoke in

20124-543: The list of "contacts whose names start with A and whose pictures I have" . Similarly, more relationships could be taken into account to further narrow down the results. Further, a natural language query processor, which parses query in natural language and creates a well-formed OPath query string to search via proper relationships, can allow users to make searches such as "find the name of the wine I had with person X last month" , provided financial management applications are using WinFS to store bills. Different relations specify

20296-457: The meaning of a word by identifying all its semantic features. A semantic or lexical field is a group of words that are all related to the same activity or subject. For instance, the semantic field of cooking includes words like bake , boil , spice , and pan . The context of an expression refers to the situation or circumstances in which it is used and includes time, location, speaker, and audience. It also encompasses other passages in

20468-446: The meaning of an expression is the part of reality to which it points. Ideational theories identify meaning with mental states like the ideas that an expression evokes in the minds of language users. According to causal theories, meaning is determined by causes and effects, which behaviorist semantics analyzes in terms of stimulus and response. Further theories of meaning include truth-conditional semantics , verificationist theories,

20640-492: The meaning of complex expressions by analyzing their parts, handling ambiguity, vagueness, and context-dependence, and using the extracted information in automatic reasoning . It forms part of computational linguistics , artificial intelligence , and cognitive science . Its applications include machine learning and machine translation . Cultural semantics studies the relation between linguistic meaning and culture. It compares conceptual structures in different languages and

20812-407: The meaning of particular expressions, like the semantics of the word fairy . As a field of inquiry, semantics has both an internal and an external side. The internal side is interested in the connection between words and the mental phenomena they evoke, like ideas and conceptual representations. The external side examines how words refer to objects in the world and under what conditions a sentence

20984-655: The meaning of the name George Washington is the person with this name. General terms refer not to a single entity but to the set of objects to which this term applies. In this regard, the meaning of the term cat is the set of all cats. Similarly, verbs usually refer to classes of actions or events and adjectives refer to properties of individuals and events. Simple referential theories face problems for meaningful expressions that have no clear referent. Names like Pegasus and Santa Claus have meaning even though they do not point to existing entities. Other difficulties concern cases in which different expressions are about

21156-421: The meaning of the words they are part of, as in inanimate and dishonest . Phrasal semantics studies the meaning of sentences. It relies on the principle of compositionality to explore how the meaning of complex expressions arises from the combination of their parts. The different parts can be analyzed as subject , predicate , or argument . The subject of a sentence usually refers to a specific entity while

21328-413: The meanings of their parts. Truth is a property of statements that accurately present the world and true statements are in accord with reality . Whether a statement is true usually depends on the relation between the statement and the rest of the world. The truth conditions of a statement are the way the world needs to be for the statement to be true. For example, it belongs to the truth conditions of

21500-492: The meanings of words combine to create the meanings of sentences?", "How do meanings relate to the minds of language users, and to the things words refer to?", and "What is the connection between what a word means, and the contexts in which it is used?". The main disciplines engaged in semantics are linguistics , semiotics , and philosophy . Besides its meaning as a field of inquiry, semantics can also refer to theories within this field, like truth-conditional semantics , and to

21672-467: The mind the frame of marriage. Conceptual semantics shares with cognitive semantics the idea of studying linguistic meaning from a psychological perspective by examining how humans conceptualize and experience the world. It holds that meaning is not about the objects to which expressions refer but about the cognitive structure of human concepts that connect thought, perception, and action. Conceptual semantics differs from cognitive semantics by introducing

21844-448: The model is that there is no direct relation between a linguistic expression and what it refers to, as was assumed by earlier dyadic models. This is expressed in the diagram by the dotted line between symbol and referent. The model holds instead that the relation between the two is mediated through a third component. For example, the term apple stands for a type of fruit but there is no direct connection between this string of letters and

22016-519: The original eight including relational comparison operators and extensions that offer support for nesting and hierarchical data, among others. Normalization was first proposed by Codd as an integral part of the relational model. It encompasses a set of procedures designed to eliminate non-simple domains (non-atomic values) and the redundancy (duplication) of data, which in turn prevents data manipulation anomalies and loss of data integrity. The most common forms of normalization applied to databases are called

22188-811: The other item via a property. So, for example, if a picture is related to a picture, it can be accessed by traversing the relationship as: An OPath query string allows to express the parameters that will be queried for to be specified using Item properties, embedded Items as well as Relationships . It can specify a single search condition, such as "title = Something'" , or a compound condition such as "title = 'Title 1' || title = 'Title 2' && author = 'Someone'" . These Boolean and relational operations can be specified using C# like && , || , = , != operators as well as their English-like equivalent like EQUAL , NOT EQUAL . SQL like operators such as LIKE , GROUP BY and ORDER BY are also supported, as are wildcard conditions. So, "title LIKE 'any*'"

22360-506: The other table. When each cell can contain only one value and the PK migrates into a regular entity table, this design pattern can represent either a one-to-one or one-to-many relationship. Most relational database designs resolve many-to-many relationships by creating an additional table that contains the PKs from both of the other entity tables – the relationship becomes an entity;

22532-408: The pillars of the "Longhorn" wave of technologies, and would ship as part of the next version of Windows. It was subsequently decided that WinFS would ship after the release of Windows Vista , but those plans were shelved in June 2006, with some of its component technologies being integrated into ADO.NET and Microsoft SQL Server . Many filesystems found on common operating systems , including

22704-446: The pre-1996 implementation of Ingres QUEL . A relational model organizes data into one or more tables (or "relations") of columns and rows , with a unique key identifying each row. Rows are also called records or tuples . Columns are also called attributes. Generally, each table/relation represents one "entity type" (such as customer or product). The rows represent instances of that type of entity (such as "Lee" or "chair") and

22876-564: The predicate describes a feature of the subject or an event in which the subject participates. Arguments provide additional information to complete the predicate. For example, in the sentence "Mary hit the ball", Mary is the subject, hit is the predicate, and the ball is an argument. A more fine-grained categorization distinguishes between different semantic roles of words, such as agent, patient, theme, location, source, and goal. Verbs usually function as predicates and often help to establish connections between different expressions to form

23048-406: The principle features Microsoft intended to provide with WinFS included a pane for metadata property editing, breadcrumb -based property navigation, filtering or stacking items over properties, incremental search , and saved searches ; these features were incorporated in Windows Vista. Query composition , a feature of WinFS that allowed users to perform additional searches that reuse the results of

23220-401: The problem of meaning from a psychological perspective or how the mind of the language user affects meaning. As a subdiscipline of cognitive linguistics , it sees language as a wide cognitive ability that is closely related to the conceptual structures used to understand and represent the world. Cognitive semanticists do not draw a sharp distinction between linguistic knowledge and knowledge of

23392-400: The programmers have to understand the structure and semantics of all the files. Using common file formats is a workaround to this problem but not a universal solution; there is no guarantee that all applications will use the format. Data with standardized schema, such as XML documents and relational data fare better, as they have a standardized structure and run-time requirements. Also,

23564-601: The pronoun you in either case. Closely related fields are intercultural semantics, cross-cultural semantics, and comparative semantics. Pragmatic semantics studies how the meaning of an expression is shaped by the situation in which it is used. It is based on the idea that communicative meaning is usually context-sensitive and depends on who participates in the exchange, what information they share, and what their intentions and background assumptions are. It focuses on communicative actions, of which linguistic expressions only form one part. Some theorists include these topics within

23736-546: The properties of individual objects. Relations are also exposed as properties. Each WinFS Item has two properties, named IncomingRelationships and OutgoingRelationships , which provide access to the set of relationship instances the item participates in. The other item which participates in one relationship instance can be reached through the proper relationship instance. The fact that the data can be accessed using its description, rather than location, can be used to provide end-user organizational capabilities without limiting to

23908-497: The public meaning that expressions have, like the meaning found in general dictionary definitions. Speaker meaning, by contrast, is the private or subjective meaning that individuals associate with expressions. It can diverge from the literal meaning, like when a person associates the word needle with pain or drugs. Meaning is often analyzed in terms of sense and reference , also referred to as intension and extension or connotation and denotation . The referent of an expression

24080-458: The referencing relation. A foreign key can be used to cross-reference tables, and it effectively uses the values of attributes in the referenced relation to restrict the domain of one or more attributes in the referencing relation. The concept is described formally as: "For all tuples in the referencing relation projected over the referencing attributes, there must exist a tuple in the referenced relation projected over those same attributes such that

24252-458: The related contacts and the relationships of the contacts with restaurant bills and dynamically generate filters like "Emails sent to people I had lunch with" . The WinFS API provides a class called the ItemContext class, which is bound to a WinFS store. The ItemContext object can be used to scope the search to the entire store or a subset of it. It also provides transactional access to

24424-450: The relation between expressions and their denotation. One of its key tasks is to provide frameworks of how language represents the world, for example, using ontological models to show how linguistic expressions map to the entities of that model. A common idea is that words refer to individual objects or groups of objects while sentences relate to events and states. Sentences are mapped to a truth value based on whether their description of

24596-489: The relation between language and meaning. Cognitive semantics examines meaning from a psychological perspective and assumes a close relation between language ability and the conceptual structures used to understand the world. Other branches of semantics include conceptual semantics , computational semantics , and cultural semantics. Theories of meaning are general explanations of the nature of meaning and how expressions are endowed with it. According to referential theories ,

24768-400: The relational model were from: The most common definition of an RDBMS is a product that presents a view of data as a collection of rows and columns, even if it is not based strictly upon relational theory . By this definition, RDBMS products typically implement some but not all of Codd's 12 rules. A second school of thought argues that if a database does not implement all of Codd's rules (or

24940-575: The relationships. WinFS includes mappings for object and XML schemas by default. Mappings for other schemas must be specified. Object schemas are specified in XML; WinFS generates code to surface the schemas as .NET classes . ADO.NET can be used to directly specify the relational schema, though a mapping to the object schema must be provided to surface it as classes. Relationship traversals are performed as joins on these tables. WinFS also automatically creates indexes on these tables, to enable fast access to

25112-594: The relevant part of the index fits into memory). Queries made against the relational database, and the derived relvars in the database are expressed in a relational calculus or a relational algebra . In his original relational algebra, Codd introduced eight relational operators in two groups of four operators each. The first four operators were based on the traditional mathematical set operations : The remaining operators proposed by Codd involve special operations specific to relational databases: Other operators have been introduced or proposed since Codd's introduction of

25284-399: The resolution table is then named appropriately and the two FKs are combined to form a PK. The migration of PKs to other tables is the second major reason why system-assigned integers are used normally as PKs; there is usually neither efficiency nor clarity in migrating a bunch of other types of columns. Relationships are a logical connection between different tables (entities), established on

25456-403: The role of object language and metalanguage at the same time. This is the case in monolingual English dictionaries , in which both the entry term belonging to the object language and the definition text belonging to the metalanguage are taken from the English language. Lexical semantics is the sub-field of semantics that studies word meaning. It examines semantic aspects of individual words and

25628-435: The same attributes . A tuple usually represents an object and information about that object. Objects are typically physical objects or concepts. A relation is usually described as a table , which is organized into rows and columns . All the data referenced by an attribute are in the same domain and conform to the same constraints. The relational model specifies that the tuples of a relation have no specific order and that

25800-402: The same entity. For instance, the expressions Roger Bannister and the first man to run a four-minute mile refer to the same person but do not mean exactly the same thing. This is particularly relevant when talking about beliefs since a person may understand both expressions without knowing that they point to the same entity. A further problem is given by expressions whose meaning depends on

25972-412: The same proposition, like the English sentence "the tree is green" and the German sentence "der Baum ist grün" . Utterance meaning is studied by pragmatics and is about the meaning of an expression on a particular occasion. Sentence meaning and utterance meaning come apart in cases where expressions are used in a non-literal way, as is often the case with irony . Semantics is primarily interested in

26144-427: The same spelling are homonyms , like a bank of a river in contrast to a bank as a financial institution. Hyponymy is closely related to meronymy , which describes the relation between part and whole. For instance, wheel is a meronym of car . An expression is ambiguous if it has more than one possible meaning. In some cases, it is possible to disambiguate them to discern the intended meaning. The term polysemy

26316-440: The scope of semantics while others consider them part of the distinct discipline of pragmatics. Theories of meaning explain what meaning is, what meaning an expression has, and how the relation between expression and meaning is established. Referential theories state that the meaning of an expression is the entity to which it points. The meaning of singular terms like names is the individual to which they refer. For example,

26488-410: The sentence "it is raining outside" that raindrops are falling from the sky. The sentence is true if it is used in a situation in which the truth conditions are fulfilled, i.e., if there is actually rain outside. Truth conditions play a central role in semantics and some theories rely exclusively on truth conditions to analyze meaning. To understand a statement usually implies that one has an idea about

26660-460: The standard declarative SQL syntax. Stored procedures are not part of the relational database model, but all commercial implementations include them. An index is one way of providing quicker access to data. Indices can be created on any combination of attributes on a relation . Queries that filter using those attributes can find matching tuples directly using the index (similar to Hash table lookup), without having to check each tuple in turn. This

26832-449: The store. An object of this class can then spawn an ItemSearcher object which then takes the type (an object representing the type) of the item to be retrieved or the relationship and the OPath query string representing the criteria for the search. A set of all matches is returned, which can then be bound to a UI widget for displaying en masse or enumerating individually. The properties items can also be modified and then stored back to

27004-472: The structure of the data items that will be stored in WinFS, must be supplied to the WinFS runtime beforehand. In Beta 1 of WinFS, the schema assembly had to be added to the GAC before it could be used. WinFS models data using the data items, along with their relationships , extensions and rules governing its usage. WinFS needs to understand the type and structure of the data items, so that the information stored in

27176-500: The synchronization components into Microsoft Sync Framework . In 2013 Bill Gates cited WinFS as his greatest disappointment at Microsoft and that the idea of WinFS was ahead of its time, which will re-emerge. WinFS uses a relational engine, which derives from SQL Server 2005, to provide the data-relations mechanism. WinFS stores are simply SQL Server database (.MDF) files with the FILESTREAM attribute set. These files are stored in

27348-509: The system are instances of the data type recognized by the WinFS runtime. The data are structured by means of properties. For example, an instance of a résumé type will surface the data by exposing properties, such as Name , Educational Qualification , Experience . Each property may be a simple type ( strings , integers , dates ) or complex types ( contacts ). Different data types expose different properties. Besides that, WinFS also allows different data instances to be related together; such as

27520-767: The tuple contains a candidate or primary key then obviously it is unique; however, a primary key need not be defined for a row or record to be a tuple. The definition of a tuple requires that it be unique, but does not require a primary key to be defined. Because a tuple is unique, its attributes by definition constitute a superkey . All data are stored and accessed via relations . Relations that store data are called "base relations", and in implementations are called "tables". Other relations do not store data, but are computed by applying relational operations to other relations. These relations are sometimes called "derived relations". In implementations these are called " views " or "queries". Derived relations are convenient in that they act as

27692-473: The tuples, in turn, impose no order on the attributes. Applications access data by specifying queries, which use operations such as select to identify tuples, project to identify attributes, and join to combine relations. Relations can be modified using the insert , delete , and update operators. New tuples can supply explicit values or be derived from a query. Similarly, queries identify tuples for updating or deleting. Tuples by definition are unique. If

27864-401: The unique key of the linked row (such columns are known as foreign keys ). Codd showed that data relationships of arbitrary complexity can be represented by a simple set of concepts. Part of this processing involves consistently being able to select or modify one and only one row in a table. Therefore, most physical implementations have a unique primary key (PK) for each row in a table. When

28036-422: The unstructured components as files while storing the structured metadata in the structured store. Internally, WinFS uses a relational database to manage data. It does not limit the data to belonging to any particular data model. The WinFS runtime maps the schema to a relational modality, by defining the tables it will store the types in and the primary keys and foreign keys that would be required to represent

28208-689: The values in each of the referencing attributes match the corresponding values in the referenced attributes." A stored procedure is executable code that is associated with, and generally stored in, the database. Stored procedures usually collect and customize common operations, like inserting a tuple into a relation , gathering statistical information about usage patterns, or encapsulating complex business logic and calculations. Frequently they are used as an application programming interface (API) for security or simplicity. Implementations of stored procedures on SQL RDBMS's often allow developers to take advantage of procedural extensions (often vendor-specific) to

28380-407: The word dog is associated with the concept of the four-legged domestic animal. Sentence meaning falls into the field of phrasal semantics and concerns the denotation of full sentences. It usually expresses a concept applying to a type of situation, as in the sentence "the dog has ruined my blue skirt". The meaning of a sentence is often referred to as a proposition . Different sentences can express

28552-432: The world and see them instead as interrelated phenomena. They study how the interaction between language and human cognition affects the conceptual organization in very general domains like space, time, causation, and action. The contrast between profile and base is sometimes used to articulate the underlying knowledge structure. The profile of a linguistic expression is the aspect of the knowledge structure that it brings to

28724-542: The world is in correspondence with its ontological model. Formal semantics further examines how to use formal mechanisms to represent linguistic phenomena such as quantification , intensionality , noun phrases , plurals , mass terms, tense , and modality . Montague semantics is an early and influential theory in formal semantics that provides a detailed analysis of how the English language can be represented using mathematical logic. It relies on higher-order logic , lambda calculus , and type theory to show how meaning

28896-787: Was conceived to be launched with SQL Server 2000. However, SQL Server 2000 ended up being a minor upgrade to SQL Server 7.0 and RFS was not implemented. The concept was not scrapped, and served as the base for WinFS. WinFS was initially planned for inclusion in Windows Vista , and build 4051 of Windows Vista, then called by its codename "Longhorn", given to developers at the Microsoft Professional Developers Conference in 2003, included WinFS, but it suffered from significant performance issues. In August 2004, Microsoft announced that WinFS would not ship with Windows Vista; it would instead be available as

29068-642: Was designed by a workgroup within IBM in the period 1988 to 1994. DRDA enables network connected relational databases to cooperate to fulfill SQL requests. The messages, protocols, and structural components of DRDA are defined by the Distributed Data Management Architecture . According to DB-Engines , in January 2023 the most popular systems on the db-engines.com web site were: According to research company Gartner , in 2011,

29240-412: Was released in 1979 by Relational Software, now Oracle Corporation . Ingres and IBM BS12 followed. Other examples of an RDBMS include IBM Db2 , SAP Sybase ASE , and Informix . In 1984, the first RDBMS for Macintosh began being developed, code-named Silver Surfer, and was released in 1987 as 4th Dimension and known today as 4D. The first systems that were relatively faithful implementations of

29412-492: Was supposed to be included as part of Cairo . OFS was supposed to have powerful data aggregation features, but the Cairo project was shelved, and with it OFS. However, later during the development of COM , a storage system, called Storage+, based on then-upcoming SQL Server 8.0, was planned, which was slated to offer similar aggregation features. This, too, never materialized, and a similar technology, Relational File System (RFS),

29584-410: Was supposed to include integration with Windows Desktop Search , so that search results include results from both regular files and WinFS stores, as well as allow access of WinFS data using ADO.NET . On June 23, 2006, the WinFS team at Microsoft announced that WinFS would no longer be delivered as a separate product, and some components would be brought under the umbrella of other technologies. Many of

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