GilaMonster (2/19/2010)
sanketahir1985 (2/19/2010)
Obviously first onebecause in first query both the table will be scanned only for condition a.name=b.name
In second query whole table2 will be scanned then it will be compared with table1.
Are you sure about that?
The query optimiser is not stupid. It is capable of recognising that the IN is a condition, just like the inner join, and optimising appropriately. In the absence of other conditions, it's likely that both tables will be scanned regardless (unless one of them is very, very small)
thats why i said it depends on the table size too
Sanket Ahir
Don't run behind the success, Try to be eligible & success will run behind u......