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Operator Table. a Table name: bb user
b.Table Structure:
Field Name Type Remarks.
user group varchar operator group.
user name varchar operator name.
User Code Varchar Operator.
User Password varchar Operator password.
user type integer flag (1: use; -1: Repeal).
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The data dictionary is as follows:A data dictionary is a definition and description of data items, data structures, data flows, data storage, processing logic, external entities, etc., and its purpose is to make detailed descriptions of each element in a data flow diagram.
The most important role of a data dictionary is as a tool for the analysis phase. The most important use of any dictionary is to query the interpretation of items that are not understood, and in structured analysis, the role of a data dictionary is to define and explain each component of the data flow diagram.
Introduction:
The database data dictionary is not only the center of every database, but it is also very important information for each user. Users can use SQL statements to access database data dictionaries, such as data items, data structures, data flows, data storage, and processing procedures. A data dictionary is an important part of a database.
It holds information about the database and is a set of read-only tables for the user.
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Data Dictionary. An important part of the database is the data dictionary. It stores the information used by the database and is a set of read-only tables for the user. The data dictionary content includes:
Split the information of all schema objects in the database, such as tables, views, clusters, and indexes.
How much space is allocated, how much space is currently used, etc.
The default value for the column.
Constrain the integrity of the information.
The user's first name.
Permissions granted to users and roles.
Audit information accessed or used by the user.
Other generated database information.
A database data dictionary is a set of table and view structures. They are stored in the system tablespace.
The database data dictionary is not only the center of every database. And it's also very important information for every user. Users can access the database data dictionary with SQL statements.
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The role of data dictionaries and writing requirements.
A data dictionary is a tool that defines and illustrates each component of a data flow diagram. The function of a data dictionary is to explain in detail the logical content and characteristics of various components in a data flow diagram, including data items, data structures, data flows, data storage, processing functions, external items, etc. The detailed information about the system in the data dictionary is an important basis for future system design, system implementation and maintenance.
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1. The concept of data dictionary.
A data dictionary is a record that can be accessed by users to record metadata about databases and applications. Generally, it can be divided into active data dictionaries and passive data dictionaries. An active data dictionary whose contents can be automatically updated when changes are made to the database or application structure.
Passive data dictionaries, whose contents must be manually updated when modified.
2. Users of data dictionaries.
A data dictionary is a description of data, a collection of data objects or item descriptions in a data model. Data dictionaries are beneficial for developers, analysts, algorithm engineers, and other users who need to refer to the data at a faster speed.
When developers use data model programs, a data dictionary can help understand where a data item fits into the structure, what numeric values it might contain, and what it means to represent reality.
For example, when we see academic qualifications, we see that when we need to know the specific meaning, we can know from the dictionary that 01 means elementary school, 02 means junior high school, and 03 means high school.
In short, the goal of the data dictionary is to better integrate and integrate the company's data assets, and it is also a comprehensive combing of the business.
In addition to technical developers, there are analysts, algorithm engineers, risk control strategy engineers, including business operation personnel, and can also query data assets that can be used according to business development to help better expand business. What you can see from the data dictionary is not only the explanation of the data fields, but also the meaning of the business.
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