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Best practice: EXISTS vs COL_NAME in
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Forum:
Microsoft SQL Server
Catégorie:
Syntaxe SQL
Titre:
Best practice: EXISTS vs COL_NAME in
Versions des environnements
SQL Server:
SQL Server 2005
Divers
Thread ID:
01464472
Message ID:
01464472
Vues:
131
Hi,

What is a better practice and more efficient when using a derived table in a SQL Select:
select Table1.* T1 where exists (select * from Table2 T2 where T1.pk_fld = T2.pk_fld and T2.fld2 = '123')
vs
select Table1.* T1 where T1.pk_fld in (select pk_fld from Table2 T2 where T1.pk_fld = T2.pk_fld and T2.fld2 = '123')
TIA
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