Question

I’m using SQL Server 2008 and would like to know if there is a way to write a generic update trigger that checks to see if the table being updated has a field called ‘Last_Updated’ and if so updates that field with the getDate() function.

Can I write a single generic trigger like that that that works for all tables in my db?

Thanks for your time!

Answer 1

no, you need to have a trigger for each table, or include Last_Updated=GETDATE in every UPDATE.

try this:

SELECT 
    'CREATE TRIGGER [tr_u_'+TABLE_SCHEMA+'_'+TABLE_NAME+'] ON ['+TABLE_SCHEMA+'].['+TABLE_NAME+']'
        +'AFTER UPDATE AS '
        +'UPDATE ['+TABLE_SCHEMA+'].['+TABLE_NAME+'] '
        +'    SET Last_Updated=GETDATE() '
        +'    FROM ['+TABLE_SCHEMA+'].['+TABLE_NAME+']  A '
        +'    INNER JOIN INSERTED  i ON a.pk=i.pk '
    FROM INFORMATION_SCHEMA.COLUMNS 
    WHERE COLUMN_NAME='LastChgDate' --'Last_Updated'

This query will produce a Create Trigger command for every table that has a Last_Updated column. You MUST edit each command and and fix the a.pk=i.pk for each table to be the proper columns. Then run all the commands and then you’ll have all the triggers. you’ll need to add triggers as you add new tables.