1 语法
SQL> desc userinfo_c3
名称是否为空?类型
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ID NOT NULL VARCHAR2(10)
USERNAME VARCHAR2(20)
SALARY NUMBER(5)
SQL>select constraint_name,constraint_type,status from user_constraints
2where table_name='USERINFO_C3';
CONSTRAINT_NAME C STATUS
---------------------------------------
SYS_C0011123 P ENABLED
CK_SALARY_NEW C ENABLED
SQL> alter table userinfo_c3
2 disable constraint CK_SALARY_NEW;
表已更改。
SQL>select constraint_name,constraint_type,status from user_constraints
2where table_name='USERINFO_C3';
CONSTRAINT_NAME C STATUS
---------------------------------------
SYS_C0011123 P ENABLED
CK_SALARY_NEW C DISABLED
SQL> alter table userinfo_c3
2 drop constraint CK_SALARY_NEW;
表已更改。