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This article is to share with you what the sql language has. The editor thought it was very practical, so I shared it with you as a reference. Let's follow the editor and have a look.

Sql language includes: data query language, data manipulation language, transaction language, data control language, data definition language and pointer control language.

1. Data query language (DQL)

Its statement, also known as a "data retrieval statement", is used to obtain data from a table and determine how the data is given in the application. The reserved word SELECT is the most frequently used verb in DQL (and all SQL). Other commonly used reserved words in DQL are WHERE,ORDER BY, GROUP BY and HAVING. These DQL reserved words are often used with other types of SQL statements.

2. Data manipulation language (DML)

Its statements include INSERT,UPDATE and DELETE. Used to add, modify, and delete records in the table, respectively. Also known as Action query language.

3. Transaction processing language (TPL)

Its statement ensures that all rows of the table affected by the DML statement are updated in a timely manner. TPL statements include BEGIN TRANSACTION,COMMIT and ROLLBACK.

Data Control language (DCL)

Its statements are licensed through GRANT or REVOKE to determine the access of individual users and user groups to database objects. Some RDBMS can use GRANT or REVOKE to control access to individual columns of the form.

5. Data definition language (DDL)

Its sentences include verbs CREATE and DROP, ALTER. Create a new table or delete a table (CREATE TABLE or DROP TABLE or ALTER TABLE) in the database; manipulate the structure of the table to add an index to the table.

6. Pointer Control language (CCL)

Its statements, such as DECLARE CURSOR, FETCH INTO, and UPDATE WHERE CURRENT, are used for single-line (record) operations on one or more forms.

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