oracle删除主键查看主键约束及创建联合主键

ALTER TABLE TABLENAME DROP PRIMARY_KEY执行上面的SQL可以删除主键；如果不成功可以用ALTER TABLE TABLENAME DROP CONSTRAINTS COLUMN CASCADE; --删除约束ALTER TABLE TABLENAME DISABLE PRIMARY_COLUMN ; --设置被设置为主键的列为无效DROP INDEX INDEX_NAME; --删除主键索引

SELECT * FROM USER_CONSTRAINTS WHERE CONSTRAINT_TYPE='P' AND TABLE_NAME='你要查看的表名' AND OWNER=USER

ALTER TABLE ADD CONSTRAINTS '约束名' PRIMARY KEY (COLUMN,COLUMN,...);