1. Add fields in different positions in mysql Add
fields (add after a specific field)
alter table table name add information that needs to be modified/added afer field name (add after which field)
alter table dept Add column name varchar(20) not null default 0 AFTER sex;
Add a field (add the field at the first position)
alter table table name add information that needs to be modified/added first;
alter table dept Add column name varchar(20) not null default 0 first;
2. Modify the field name
alter table table name change the field name field type of the original field to be modified;
alter table dept change name newname varchar(30);
3. Delete the field:
alter table table name drop column column name
alter table user_movement_log drop column Gatewayid;
4. Adjust the field order:
ALTER TABLE user_movement_log CHANGE GatewayId GatewayId int not null default 0 AFTER RegionID;
at last
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