100.
Can "order by" clause use index to increase performance of search?
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Available indexes for ORDER BY clause
If you want to speed up a "live" SELECT from a single table with ORDER BY clause, you can create a compound index for ORDER BY fields.
For example if you would like to increase the speed of the query:
SELECT * FROM Employee ORDER BY LastName, FirstName
you can do it by creating the following compound index:
ABSTable1.AddIndex('idxLastNameFirstName', 'LastName;FirstName', []);