sql server - SQL - update, delete, insert - Whatif scenerio -

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i reading article other day showed how run sql update, insert, or deletes whatif type scenario. don't remember parameter talked , can't find article. not sure if dreaming.

anyway, know if there parameter in sql2008 lets try insert, update, or delete without committing it? log or show have updated. remove parameter , run if behaves expect.

i don't know of sql2008 specific feature sql service supports transactions can this:

  1. start transaction ("begin transaction" in tsql)
  2. the rest of insert/update/delete/what-ever code
  3. (optional) select statements , such if needed output result of above actions, if default output step 2 (things "x rows affected") not enough
  4. rollback transaction ("rollback transaction" in tsql)
  5. (optional) repeat testing code show how things without code in step 2 having run

for example:

begin transaction -- make changes delete people name 'x%' delete people name 'd%' exec some_proc_that_does_more_work -- check db state after changes select count(*) people -- undo rollback transaction -- confirm db state without changes select count(*) people

(you might prefer optional "confirm" step before starting transaction rather after rolling back, i've done way around keeps 2 likely-to-be-identical sections of code easier editing)

if use rather sql2008 specific technique should transferable other rdbs (just update syntax if needed).


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