What DML, DDL, DCL that?

A, DML

　　DML (data manipulation language) data manipulation language:

　　　　We often use the INSERT, DELETE, UPDATE, SELECT statements. Mainly used for some data in the database operation.

The INSERT  the INTO table_name (column 1, column 2, ...) the VALUES (value 1, value 2, ....)
 the DELETE  the FROM table name WHERE column name = value
 UPDATE table name SET column name = the new value WHERE column name = a value
 SELECT column names FROM table name

Two, DDL

　　DDL (data definition language) database definition language, such as:

　　CREATE: create

　　 ALTER: modify the table structure

　　 RENAME: Modify the table or column name

　　 DROP: When you delete the table structure and data, delete can not be rolled back

　　 TRUNCATE: delete data in the table without deleting the table structure, it can not be rolled back after deletion efficient than DELETE

　　In fact, what we used when creating the table some sql, for example: CREATE, ALTER, DROP and so on. DDL is mainly used in the structure or changing the definition table, the data type, the link between the tables and constraints initialization work

The CREATE  TABLE table name 
( 
Column Name Data Type 1, 
column 2 the data type name, 
column name data type 3, 
.... 
) 

the ALTER  TABLE table_name
 the ALTER  the COLUMN column_name DataType 

the DROP  TABLE table name
 the DROP  DATABASE database name

Three, DCL

　　DCL (Data Control Language) database control language:

　　　　It is used to set or change the database user or role privileges statements, such as:

　　　　1) GRANT: Authorization

　　　　2) REVOKE: Recycling authority

What DML, DDL, DCL that?

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