[Linux] [MySQL] command change table structure: Add, delete, modify fields, adjust field order

Source: Internet
Author: User
Tags mysql commands

Original source: http://www.phpernote.com/MySQL/1120.html

1 frequently used MySQL commands to change the table structure of some SQL statements, including adding, deleting, modifying fields, adjusting the order of the fields. 2 3 To Add a field:4 5ALTER TABLE ' User_movement_log ' Add column Gatewayid int notNULL default0After ' RegionID '; (which field is added later)6 7 To delete a field:8 9 ALTER TABLE ' user_movement_log ' drop column Gatewayid;Ten  One To adjust the order of fields: A  -ALTER TABLE ' user_movement_log ' Change ' Gatewayid ' "Gatewayid ' int notNULL default0After RegionID; -  the //PRIMARY Key -  -ALTER TABLE tabelname add new_field_id int (5) unsigneddefault0 notNULLAuto_increment, add PrimaryKey(new_field_id); -  + //Add a new column -  + ALTER TABLE T2 add d timestamp; AALTER TABLE infos add ex tinyint notNULL default' 0 '; at  - //Delete Column -  - ALTER TABLE T2 drop column C; -  - //Renaming Columns in  -ALTER TABLE T1 change a Binteger; to  + //changing the type of a column -  theALTER TABLE T1 change b b bigint notNULL; *ALTER TABLE infos changeList Listtinyint notNULL default' 0 '; $ Panax Notoginseng //Renaming a table -  theALTER TABLE T1RenameT2; +  A Gazzo Primer the  + MySQL> ALTER TABLE tablename change depno depno int (5) notNULL; - MySQL>ALTER TABLE tablename ADD index index name (field name 1[, field Name 2 ...]); $ MySQL>ALTER TABLE tablename Add index Emp_name (name); $  - index of the plus primary keyword -  the MySQL> ALTER TABLE tablename Add primaryKey(ID); - Wuyi index with unique restriction criteria the  - MySQL>ALTER TABLE tablename add unique emp_name2 (cardnumber); Wu  - Delete an index About  $ MySQL>ALTER TABLE tablename DROP INDEX emp_name; -  - To Modify a table: -  A Add Field: +  the MySQL>ALTER TABLE table_name ADD field_name field_type; -  $ Modify the original field name and type: the  the MySQL>ALTER TABLE table_name change old_field_name new_field_name field_type; the  the To delete a field: -  in MySQL> ALTER TABLE table_name DROP field_name;

[Linux] [MySQL] command change table structure: Add, delete, modify fields, adjust field order

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