logical database design

three situations:, 1: N, and M: N. 7) The link mode with the same code can be merged. In order to further improve the performance of the database application system, the data model structure should be modified and adjusted appropriately under the guidance of standardization theory. This is the optimization of the data model. Determine the data dependency. Eliminate redundant connections. Determine which relationship modes belong to the nth paradigm.

same code can be merged. In order to further improve the performance of the database application system, the data model structure should be modified and adjusted appropriately under the guidance of standardization theory. This is the optimization of the data model. Determine the data dependency. Eliminate redundant connections. Determine which relationship modes belong to the nth paradigm. Determine whether to merge or break them down. In general, th

Database Design-semi-structured storage and database structured storage Business scenario: the user fills in some documents, reports them, and approves them. There are several fields in the document that need statistics, and the business is not complicated. In a seemingly simple scenario, when the developer came up with the PDM

model: Also known as the information model, it is based on the user's point of view of data and information modeling, for database design. 　　　　Logical models and Physical models: The main types of logical models include mesh models, hierarchical models, relational models, object-oriented models, and so on. According t

specific DBMS is formed by integrating, summarizing, and abstracting user requirements.3. Logical Structure Design StageConverts a conceptual structure to a data model supported by a DBMS.Optimize it4. Physical database design phaseSelect a physical structure (including storage structure and access method) that best s

supported in the model of E-rwin design, so the relationship is paid attention to when the model of E-rwin diagram is converted to PowerDesigner model. The physical realization of the logical model in the database physical diagram embodies the reference relationship between the tables. It is impossible to have a many-to-many relationship in a physical model. Wh

How many stages are there in Database Design? Strictly speaking, there are more than three stages. Today we will only discuss three of them. Concept Design, logical design, and physical design. First, we need to clarify a few ques

single attribute is composed of basic types, including integer, real, character, logical, date, etc.For example, the following database tables are consistent with the first paradigm: Field 1 Field 2 Field 3 Field 4 and such a database table is inconsistent with the first paradigm: Field 1

Get the analysis finished product demand is the line design UML (with class diagram) or the first design database? Reply content: Get the analysis finished product demand is the line design UML (with class diagram) or the first design

The database design method can be divided into four categories: visual design method, normative design method, CAD method and automatic design method. Among them, the New Orleans method is a kind of normative design method, which

Label: Database Paradigm when designing the relational database, we should design a reasonable relational database to conform to different specifications, and the different norm requirements are called different paradigms, and the higher paradigm database