Oracle中用表外键来保证系统参照完整性

SELECT 'ALTER TABLE ' || TABLE_NAME ||' '|| 

'DROP CONSTRAINT ' || CONSTRAINT_NAME || ' ;' 

FROM USER_CONSTRAINTS 

WHERE CONSTRAINT_NAME LIKE 'SYS%' AND 

CONSTRAINT_TYPE = 'R';

ALTER TABLE DJ_NSRXX DROP CONSTRAINT SYS_C000231;

SELECT 'ALTER TABLE ' || child.TABLE_NAME||' ' || 

'ADD CONSTRAINT ' || ' 外键名称 ' ||' '|| 

'FOREIGN KEY ' || '('|| cp.COLUMN_NAME || ')' || 

' '|| 'REFERENCES ' || parent.TABLE_NAME ||' '|| 

'('|| pc.COLUMN_NAME || ')'|| child.DELETE_RULE || ' ;' 

FROM USER_CONSTRAINTS child, 

USER_CONSTRAINTS parent, 

USER_CONS_COLUMNS cp, 

USER_CONS_COLUMNS pc 

WHERE child.CONSTRAINT_TYPE = 'R' AND 

child.R_OWNER = PARENT.OWNER AND 

child.R_CONSTRAINT_NAME = PARENT.CONSTRAINT_NAME AND 

child.CONSTRAINT_NAME = cp.CONSTRAINT_NAME AND 

parent.CONSTRAINT_NAME = pc.CONSTRAINT_NAME AND 

cp.POSITION = pc.POSITION AND 

child.CONSTRAINT_NAME LIKE 'SYS%' 

ORDER BY child.OWNER, 

child.TABLE_NAME, 

child.CONSTRAINT_NAME, 

cp.POSITION;

ALTER TABLE DJ_NSRXX ADD CONSTRAINT 外键名称
 FOREIGN KEY (RYDM) REFERENCES DM_GY_SWRY(RYDM);

ALTER TABLE DJ_NSRXX ADD CONSTRAINT FK_DJ_NSRXX_DM_GY_SWRY 
FOREIGN KEY (RYDM) REFERENCES DM_GY_SWRY(RYDM);