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	works with a new policy in cascade mode . Please Read README.MAX . I do not know if you are the author of refint.c , but if not please tell me who is . Thank you ( excuse me for my bad english) . Massimo Lambertini massimo.lambertini@everex.it
		
			
				
	
	
		
			69 lines
		
	
	
		
			1.5 KiB
		
	
	
	
		
			SQL
		
	
	
	
	
	
			
		
		
	
	
			69 lines
		
	
	
		
			1.5 KiB
		
	
	
	
		
			SQL
		
	
	
	
	
	
| --Column ID of table A is primary key:
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| 
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| CREATE TABLE A (
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| 	ID	int4 not null,
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| 	id1	int4 not null,
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| primary key (ID,ID1)
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| );
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| 
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| --Columns REFB of table B and REFC of C are foreign keys referenting ID of A:
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| 
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| CREATE TABLE B (
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| 	REFB	int4,
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| 	REFB1	INT4
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| );
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| CREATE INDEX BI ON B (REFB);
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| 
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| CREATE TABLE C (
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| 	REFC	int4,
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| 	REFC1	int4
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| );
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| CREATE INDEX CI ON C (REFC);
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| 
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| --Trigger for table A:
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| 
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| CREATE TRIGGER AT BEFORE DELETE  ON A FOR EACH ROW
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| EXECUTE PROCEDURE 
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| check_foreign_key (2, 'cascade', 'ID','id1', 'B', 'REFB','REFB1', 'C', 'REFC','REFC1');
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| 
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| 
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| CREATE TRIGGER AT1  AFTER UPDATE  ON A FOR EACH ROW
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| EXECUTE PROCEDURE 
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| check_foreign_key (2, 'cascade', 'ID','id1', 'B', 'REFB','REFB1', 'C', 'REFC','REFC1');
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| 
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| 
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| CREATE TRIGGER BT BEFORE INSERT OR UPDATE ON B FOR EACH ROW
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| EXECUTE PROCEDURE 
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| check_primary_key ('REFB','REFB1', 'A', 'ID','ID1');
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| 
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| CREATE TRIGGER CT BEFORE INSERT OR UPDATE ON C FOR EACH ROW
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| EXECUTE PROCEDURE 
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| check_primary_key ('REFC','REFC1', 'A', 'ID','ID1');
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| 
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| 
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| 
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| -- Now try
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| 
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| INSERT INTO A VALUES (10,10);
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| INSERT INTO A VALUES (20,20);
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| INSERT INTO A VALUES (30,30);
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| INSERT INTO A VALUES (40,41);
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| INSERT INTO A VALUES (50,50);
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| 
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| INSERT INTO B VALUES (1);	-- invalid reference
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| INSERT INTO B VALUES (10,10);
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| INSERT INTO B VALUES (30,30);
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| INSERT INTO B VALUES (30,30);
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| 
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| INSERT INTO C VALUES (11);	-- invalid reference
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| INSERT INTO C VALUES (20,20);
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| INSERT INTO C VALUES (20,21);
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| INSERT INTO C VALUES (30,30);
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| 
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| -- now update work well 
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| update  A set ID = 100 , ID1 = 199 where ID=30 ;
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| 
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| SELECT * FROM A;
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| SELECT * FROM B;
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| SELECT * FROM C;
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