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ALTER TABLE table_name DISABLE CONSTRAINT constraint_name; |
ALTER TABLE policies DISABLE CONSTRAINT chk_gender |
ALTER TABLE policies ENABLE CONSTRAINT chk_gender |
ALTER TABLE table_name DROP CONSTRAINT constraint_name |
ALTER TABLE policies DROP CONSTRAINT chk_gender; |
CONSTRAINT [constraint_name] CHECK (condition); |
CREATE TABLE policies (policy_id NUMBER, holder_name VARCHAR2(40), gender VARCHAR2(1) constraint chk_gender CHECK (gender in ('M','F'), marital_status VARCHAR2(1), date_of_birth DATE, constraint chk_marital CHECK (marital_status in('S','M','D','W')) ); |
CREATE TABLE policies (policy_id NUMBER, holder_name VARCHAR2(40) NOT NULL, gender VARCHAR2(1), marital_status VARCHAR2(1), date_of_birth DATE NOT NULL ); |
ALTER TABLE policies MODIFY holder_name NOT NULL |
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