 <p>If I execute the query with an AND, even then , both the tables are accessed</p> <p>SET STATISTICS IO ON IF EXISTS (SELECT * from master..spt_values where [name] = 'rpcc') and EXISTS(SELECT * from master..spt_monitor where pack_sent = 5235252) PRINT 'Y' </p> <p>Table 'spt_monitor'. Scan count 1, logical reads 1, physical reads 0, read-ahead reads 0, lob logical reads 0, lob physical reads 0, lob read-ahead reads 0. Table 'spt_values'. Scan count 1, logical reads 17, physical reads 0, read-ahead reads 0, lob logical reads 0, lob physical reads 0, lob read-ahead reads 0.</p>