SQL Server/T-SQL/Trigger/UPDATE function
Using IF UPDATE() in a Trigger
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8> 9> CREATE TABLE employee( 10> id INTEGER NOT NULL PRIMARY KEY, 11> first_name VARCHAR(10), 12> last_name VARCHAR(10), 13> salary DECIMAL(10,2), 14> start_Date DATETIME, 15> region VARCHAR(10), 16> city VARCHAR(20), 17> managerid INTEGER 18> ); 19> GO 1> INSERT INTO employee VALUES (1, "Jason" , "Martin", 5890,"2005-03-22","North","Vancouver",3); 2> GO (1 rows affected) 1> INSERT INTO employee VALUES (2, "Alison", "Mathews",4789,"2003-07-21","South","Utown",4); 2> GO (1 rows affected) 1> INSERT INTO employee VALUES (3, "James" , "Smith", 6678,"2001-12-01","North","Paris",5); 2> GO (1 rows affected) 1> INSERT INTO employee VALUES (4, "Celia" , "Rice", 5567,"2006-03-03","South","London",6); 2> GO (1 rows affected) 1> INSERT INTO employee VALUES (5, "Robert", "Black", 4467,"2004-07-02","East","Newton",7); 2> GO (1 rows affected) 1> INSERT INTO employee VALUES (6, "Linda" , "Green" , 6456,"2002-05-19","East","Calgary",8); 2> GO (1 rows affected) 1> INSERT INTO employee VALUES (7, "David" , "Larry", 5345,"2008-03-18","West","New York",9); 2> GO (1 rows affected) 1> INSERT INTO employee VALUES (8, "James" , "Cat", 4234,"2007-07-17","West","Regina",9); 2> GO (1 rows affected) 1> INSERT INTO employee VALUES (9, "Joan" , "Act", 6123,"2001-04-16","North","Toronto",10); 2> GO (1 rows affected) 1> 2> select * from employee; 3> GO id first_name last_name salary start_Date region city managerid
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1 Jason Martin 5890.00 2005-03-22 00:00:00.000 North Vancouver 3 2 Alison Mathews 4789.00 2003-07-21 00:00:00.000 South Utown 4 3 James Smith 6678.00 2001-12-01 00:00:00.000 North Paris 5 4 Celia Rice 5567.00 2006-03-03 00:00:00.000 South London 6 5 Robert Black 4467.00 2004-07-02 00:00:00.000 East Newton 7 6 Linda Green 6456.00 2002-05-19 00:00:00.000 East Calgary 8 7 David Larry 5345.00 2008-03-18 00:00:00.000 West New York 9 8 James Cat 4234.00 2007-07-17 00:00:00.000 West Regina 9 9 Joan Act 6123.00 2001-04-16 00:00:00.000 North Toronto 10
(9 rows affected) 1> 2> 3> CREATE TRIGGER tru_Employee ON Employee FOR UPDATE 4> AS 5> IF @@ROWCOUNT = 0 6> RETURN 7> IF UPDATE (first_name) OR UPDATE (last_name) 8> BEGIN 9> IF EXISTS (SELECT * FROM inserted WHERE salary < 0) 10> BEGIN 11> Print "logic" 12> END 13> END 14> GO 1> 2> update employee set first_name = "" 3> 4> drop trigger tru_Employee 5> GO (9 rows affected) 1> 2> 3> drop table employee; 4> GO
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