posted 16 years ago
So Im trying to optimize this Sybase SQL query to perform faster. I did a show plan and looked for all "Table Scans" in the Plan. One by one I eliminated them all by providing index hints in the SQL itself ((index xyz_idx1).
This eliminated all the Table Scans but the perfoemance is the same. Now all of them are forward scans.
So whats the difference between a forwad scan and a table scan ?
All I knew was that Table Scans were evil. I dont really know how to interpret the elements of a SQL plan. Is there any online resource or book available that can explaion the various elements of a SQL plan ?
And finally, if a forward scan is bad performace-wise, then how do I really fix it?... im already forcing it to use the available indexes.