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作者:Crystal编译 来源:yesky 2007年10月23日
关键字: ORACLE
在本页阅读全文(共3页)
column_name data_type CONSTRAINT constraint_name UNIQUE |
CONSTRAINT constraint_name (column) UNIQUE USING INDEX TABLESPACE (tablespace_name) STORAGE (stored clause) |
CREATE TABLE insured_autos (policy_id NUMBER CONSTRAINT pk_policies PRIMARY KEY, vin VARCHAR2(10), coverage_begin DATE, coverage_term NUMBER, CONSTRAIN unique_auto UNIQUE (policy_id,vin) USING INDEX TABLESPACE index STORAGE (INITIAL 1M NEXT 10M PCTINCREASE 0) ); |
ALTER TABLE insured_autos DISABLE CONSTRAIN unique_name; |
ALTER TABLE insured_autos DROP CONSTRAIN unique_name; |
CREATE TABLE policies (policy_id NUMBER CONSTRAINT pk_policies PRIMARY KEY, holder_name VARCHAR2(40), gender VARCHAR2(1), marital_status VARCHAR2(1), date_of_birth DATE ); |
CREATE TABLE insured_autos (policy_id NUMBER, vin VARCHAR2(40), coverage_begin DATE, coverage_term NUMBER, CONSTRAINT pk_insured_autos PRIMARY KEY (policy_id,vin) USING INDEX TABLESPACE index STORAGE (INITIAL 1M NEXT 10M PCTINCREASE 0) ); |
ALTER TABLE policies DROP PRIMARY KEY; |
ALTER TABLE policies DISABLE PRIMARY KEY; |
CREATE TABLE insured_autos (policy_id NUMBER CONSTRAINT policy_fk REFERENCE policies(policy_id ON DELETE CASCADE, vin VARCHAR2(40), coverage_begin DATE, coverage_term NUMBER, make VARCHAR2(30), model VARCHAR(30), year NUMBER, CONSTRAIN auto_fk FROEIGN KEY (make,model,year) REFERENCES automobiles (make,model,year) ON DELETE SET NULL ); |
MAKE | MODEL | YEAR |
Ford | Taurus | 2000 |
Toyota | Camry | 1999 |
POLICY_ID | MAKE | MODEL | YEAR |
576 | Ford | Taurus | 2000 |
577 | Toyota | Camry | 1999 |
578 | Tucker | NULL | 1949 |
SET CONSTRAINT constraint_name|ALL DEFEERRED|IMMEDIATE --; |
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