4 relational data model section 2

The Relational Data Model and Relational Database Constraints

... Outline  Relational Model Concepts  Relational Model Constraints and Relational Database Schemas  Update Operations and Dealing with Constraint Violations Relational Model Concepts  The relational ... Model of Data is based on the concept of a Relation  A Relation is a mathematical concept based on the ideas of sets  The strength of the relational approach to data management comes from the ... by the theory of relations  We review the essentials of the relational approach in this chapter Relational Model Concepts  The model was first proposed by Dr E.F Codd of IBM in 1970 in the...
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Chương 3: Mô hình quan hệ (Relational Data Model) potx

... 20 10 Chương MÔ HÌNH QUAN HỆ II Chuyển hình ER sang hình quan hệ Bước Thuộc tính đa trò MAPB TENPB DIADIEM PHONGBAN DIADIEM_PHG (MAPB, DIADIEM) 21 Chương MÔ HÌNH QUAN HỆ II Chuyển hình ... = 1,m Chương MÔ HÌNH QUAN HỆ ĐỊNH NGHĨA QUAN HỆ • Lược đồ quan hệ (relation scheme) R(A1, A2, , An): – Trong R tên lược đồ quan hệ – A1, A2, …, An thuộc tính lược đồ quan hệ • Một quan hệ (relation) ... lược đồ quan hệ LOP Tập thuộc tính khoá ngoại không cần tương ứng tên với tập thuộc tính đóng vai trò khoá mà tham chiếu 12 Chương MÔ HÌNH QUAN HỆ II Chuyển hình ER sang hình quan hệ Bước...
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Tài liệu Activity 4.2: Creating a Logical Data Model ppt

... actions that define the relationship between each pair of entities, and label the line with the relationship verb This is the initial ER diagram for the logical data model Answer in v04_160 9a_ act42-1.bmp ... v04_160 9a_ act42-1.bmp Activity 4.2: Creating a Logical Data Model Exercise 2: Determining Cardinality and Existence In this exercise, you will use the syntax discussed in the module to identify the cardinality ... 18 Activity 4.2: Creating a Logical Data Model Exercise 1: Identifying Relationships Between Entities In this exercise, you will identify all the relationships between the entities defined in Activity...
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Tài liệu Activity 9.4: Identifying Data Access Requirements ppt

... 74 Activity 9.4: Identifying Data Access Requirements Exercise 1: Identifying a Data Access Method for a Scenario (10 minutes) ! Identify data access requirements Participate ... generated and copies to be stored in a repository for easy access in the future Solution A B Activity 9.4: Identifying Data Access Requirements 75 Exercise 2: Analyzing Technology Selection (5 ... Scenarios A All data for a new order entry system is going to be stored in Microsoft® SQL Server™ and accessed by Microsoft Excel for querying and by the Web system for additional lookups All data is...
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Tài liệu Module 4: MSF Team Model doc

... include: • Scaling the MSF Team Model • Applying the MSF Team Model v vi Module 4: MSF Team Model Background on Scaling the MSF Team Model Scaling for Small Projects Although the Team Model consists ... successful team, and the MSF Team Model Team Goals for Success The MSF Team Model Principles of a Successful Team Scaling the MSF Team Model Applying the MSF Team Model At the end of this module, ... a team of peers, which is the heart of the Team Model for application development Module 4: MSF Team Model The MSF Team Model Slide Objective To present the Team Model roles Lead-in The MSF Team...
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Tài liệu NoSQL Database Technology: Post-relational data management for interactive software systems docx

... implementations differ, NoSQL database management systems share a common set of characteristics: • No schema required Data can be inserted in a NoSQL database without first defining a rigid database schema ... necessity, forced to invent new approaches to data management These NoSQL or non-relational database technologies are a better match for the needs of modern interactive software systems But ... WWW.COUCHBASE.COM NOSQL DATABASE TECHNOLOGY • Distributed query support “Sharding” an RDBMS can reduce, or eliminate in certain cases, the ability to perform complex data queries NoSQL database systems...
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Báo cáo khoa học: "A Flexible Stand-Off Data Model with Query Language for Multi-Level Annotation" ppt

... concise way to formulate certain types of queries for multi-level annotated corpora Queries are automatically converted into the underlying query language and then executed A query in simpliﬁed ... associated query language NXT Search (Heid et al., 2004) is a powerful declarative language for querying diverse relations (incl pointers), supporting quantiﬁcation and constructs like forall and ... basedata query token consists of a regular expression in single quotes, which must exactly match one basedata element The query ’[Tt]he’ matches all deﬁnite articles, but not e.g ether or there For...
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Báo cáo khoa học: "Towards A Modular Data Model For Multi-Layer Annotated Corpora" docx

... de-facto standard representation format for annotated text corpora While the XML standard speciﬁes a data model and serialization format for XML, a semantics is largely left to be deﬁned for a particular ... annotation data from the base data and introduces references from the annotations to the base data, thus allowing to keep multiple layers of annotations on the same base data separate Today XML has ... which are identiﬁed by a name and bear a value This data model is immediately suitable for simple text annotations For example in a positional annotation, name-value pairs (features) can be assigned...
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The POSTGRES Data Model

... presents the data model Section describes the attribute type system Section describes how the query language can be extended with user-deﬁned procedures Section compares the model with other data models ... is to move the computation that constructs the mainmemory data structure to the database process Suppose the procedure MakeForm built the data structure given the name of a form Using the parameterized ... extension to the relational model is relatively straightforward and only requires a small number of changes to the DBMS implementation Other Data Models This section compares the POSTGRES data model...
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CHAPTER 3 ■ THE ENTITY DATA MODEL INSIDE AND OUT The Designer is the tool that allows you to work docx

... layer provides model customization if you like to work with XML However, there is a better way to work with the mapping and that is 56 CHAPTER THE ENTITY DATA MODEL INSIDE AND OUT discussed in ... CHAPTER THE ENTITY DATA MODEL INSIDE AND OUT EDM-Generated Classes When your EDM is created, a file is also added to the project that is auto-generated by a tool called the EntityModelCodeGenerator, ... OnBusinessEntityIDChanged(); 60 CHAPTER THE ENTITY DATA MODEL INSIDE AND OUT The Entity Framework allows you to extend these classes to add your own logic and protect the custom code you write When not...
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CollaborateChapter 4..Knowledge ByteIn this section, you will learn about: Creating partitioned doc

... Knowledge Byte In this section, you will learn about: Creating partitioned indexes System-defined stored procedures Creating Partitioned Indexes Read the following topic in the section Creating and ... task determines the boundary values for creating partitions? a Creating a partition function b Creating a partition scheme c Creating a clustered index d Creating nonclustered index NIIT Querying, ... before creating a full-text index on it? Yes, it is must to create a unique index on a table before creating a full-text index on it Can you create more that one full-text index on a table? Yes, you...
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Báo cáo y học: " XGAP: a uniform and extensible data model and software platform for genotype and phenotype experiments" potx

... directly use and adapt XGAP as a platform for their particular experimental data and analysis protocols We successfully evaluated the XGAP model and software in a broad range of experiments: array data ... MOLGENIS language and the generator automatically changes XGAP database software to your research Upload Upload data from measurement devices, public databases, collaborating XGAP databases, or a public ... experimental data using only four ‘core’ data types: Trait, Subject, Data, and DataElement For example: a single-channel microarray reports raw gene expression Data for each microarray probe Trait and...
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Báo cáo y học: "The Open Microscopy Environment (OME) Data Model and XML file: open tools for informatics and quantitative analysis in biological imaging" docx

... management and analysis system for biological microscopy The data model used by OME is represented in two distinct ways: a set of open- source software tools that use a relational database for information ... written for XML, including databases, editing tools, and parsing libraries Finally, and perhaps most important, XML is a plain-text format As a last resort, it can be opened in any text editor and ... binary image data and all information regarding the image acquisition and processing, and any results generated during analysis In this way, all aspects of the data acquisition, processing, and...
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slide cơ sở dữ liệu tiếng anh chương (4) relational algebra and Relational Calculus Transparencies

... Categories of© relational 1995, 2005 DML Introduction Relational algebra and relational calculus are formal languages associated with the relational model Informally, relational algebra is a (highlevel) ... Meaning of the term relational completeness How to form queries in relational algebra How to form queries in tuple relational calculus How to form queries in domain relational calculus Pearson Education ... language and relational calculus a non-procedural language However, formally both are equivalent to one another A language that produces a relation that can be derived using relational calculus is relationally...
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Báo cáo chuyên đề cơ sở dữ liệu nâng cao Network Data Model

... Trang: Báo cáo chuyên đề sở liệu nâng cao Đây mô hình tương tác client với database thông quan network data model II Các thành phần network data model Việc sử dụng data network model để quản lý liệu ... Báo cáo chuyên đề sở liệu nâng cao Trang kết tìm kiếm Trang thêm bạn HVTH: Nguyễn Ngọc Diễm Trang: 32 Báo cáo chuyên đề sở liệu nâng cao Xóa bạn : HVTH: Nguyễn Ngọc Diễm Trang: 33 Báo cáo chuyên ... Diễm Trang: 26 Báo cáo chuyên đề sở liệu nâng cao // Create the network object String networkName = "MY_NET"; Network myNet = NetworkFactory.createLogicalNetwork( networkName, // networkName 1,...
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