SQL Server : Multiple Where Clauses -
suppose have t-sql command multiple where
conditions this:
select * tablename column1 not '%exclude%' , column2 > 10
would query exclude row column1
not met or still go on test next condition column2
?
i asking because want see if more efficient swap conditions around first test if column2 > 10
before run more time-consuming condition.
edit: if matters, column1
of type bigint
, column2
of type ntext
sql devise query plan based on available indexes , statistics. sql doesn't have "short-circuit" expression evaluation per se because procedural language query plan perform short-circuit evaluation.
swapping expressions should not affect performance.
Comments
Post a Comment