Yes, is correct. But the expression "full table scan" is valid, even if you have no index and any query will do it every time. This is what it does, a "full table scan".
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Yes, is correct. But the expression "full table scan" is valid, even if you have no index and any query will do it every time. This is what it does, a "full table scan".
if you have some mils of rows, combined with 10s of cols => this is nightmare
So,full table scan comes into picture only when you have index created on the table(column) to make comparision.
(That is whether to make use of index or not).
If you do not have any index created on the table(column) and the selection criteria is not using that column,then full table scan will be done with select statements (irrespective of where condition).
Is this what I analyzed is correct Mr.selvan?
YES.
Tamilselvan
Vani, It seems to me you don't know much about index. I suggest you to read some thing about index before continuing this discussion.