MySQL table content modification, the brain can't remember things. Memo

MySQL adds fields, deletes fields, modifies field names, modifies field types. mysql's simple syntax, often used, but not easy to remember. Of course, these SQL syntaxes are basically common in each database. Listed below: 1. Add a field ALTER TABLE user add COLUMN new1 VARCHAR DEFAULT NULL;  Add a field that defaults to null ALTER TABLE user add COLUMN new2 VARCHAR (a) not NULL; 　 Add a field, default cannot be empty www.2cto.com 2. Delete a field ALTER TABLE user DROP COLUMN new2; 　Delete a field 3. Modify a field ALTER TABLE user MODIFY New1 VARCHAR (10);　 Modify the type of a field ALTER TABLE user change new1 new4 int; To modify the name of a field, be sure to re-specify the field's type

MySQL table content modification, the brain can't remember things. Memo