Commands to change table structure: add, delete, modify fields, adjust field order

ALTER TABLE `user_movement_log` CHANGE `GatewayId` `GatewayId` int not null default 0 AFTER RegionID;

//primary key

alter table tabelname add new_field_id int(5) unsigned default 0 not null auto_increment ,add primary key (new_field_id);

// add a new column

alter table t2 add d timestamp;

alter table infos add ex tinyint not null default '0';

// delete column

alter table t2 drop column c;

// rename the column

alter table t1 change a b integer;

 

//change the column type

alter table t1 change b b bigint not null;

alter table infos change list list tinyint not null default '0';

//rename the table

alter table t1 rename t2;

index

mysql> alter table tablename change depno depno int(5) not null;

mysql> alter table tablename add index index name (field name 1[, field name 2...]);

mysql> alter table tablename add index emp_name (name);

index with primary key

mysql> alter table tablename add primary key(id);

Index with unique constraint

mysql> alter table tablename add unique emp_name2(cardnumber);

delete an index

mysql>alter table tablename drop index emp_name;

 

Modify the table:

Add fields:

mysql> ALTER TABLE table_name ADD field_name field_type;

Modify the original field name and type:

mysql> ALTER TABLE table_name CHANGE old_field_name new_field_name field_type;

Delete fields: 

mysql> ALTER TABLE table_name DROP field_name;

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