Nine database objects in the database

To masterDatabaseFirst, we need to learn the most basic knowledge of the database. The database objects in Section 9 below will be explained as the basic knowledge of the database, it is suitable for beginners of databases. nine types of databases are summarized in this article.Database objectsIt is very comprehensive and I hope you can take it seriously.

Database objects are a component of a Database. They are common in the following ways:

1. Table)

The tables in the database are similar to the tables we use in our daily lives. They are also composed of rows) and columns. A column is composed of similar information. Each column is also called a field. The title of each column is called a field name. The row contains several column information items. A row of data is called one or more records, which express a combination of meaningful information. A database table consists of one or more records. A table without records is called an empty table. Each table usually has a primary keyword used to uniquely identify a record.

2. Index)

Indexes are created based on the specified database table column. It provides a fast way to access data, and monitors the data of the table so that the data in the column to which the index points is not repeated.

3. View)

The view looks exactly the same as the table. It has a set of named fields and data items, but it is actually a virtual table, which is not actually stored in the database. The view is generated by querying database tables, which limits the data that users can view and modify. It can be seen that the view can be used to control user access to data and simplify data display, that is, only the required data information is displayed through the view.

4. digoal)

Charts are actually the relationship between database tables. You can use it to edit the relationship between a table and a table.

5. Default Value)

The default value is to assign a pre-set value to a column or column data item without specific values when creating a column or inserting data in a table.

6. Rule)

Rules are restrictions on data information in database tables. It specifies the table columns.

7. Trigger)

A trigger is a collection of user-defined SQL transaction commands. This command is automatically executed when a table is inserted, modified, or deleted.

8. Stored Procedure)

A stored procedure is a set of SQL program statements that are compiled and stored in the database for specific functions.

9. User)

A user is a person with access permissions to the database.
 

This article introduces nine database objects in the database. If you need more basic database knowledge, I will continue to explain more basic knowledge about the database, I hope this will help you.