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Comments by Jon_Boy (Top 1 by date)

Jon_Boy 10-Jul-14 14:06pm View    
Why would Index 1 be redundant and not #2?

I found this on stackoverFlow:
Think of it this way: a compound index gives you rapid look-up of the first field in a nested set of fields followed by rapid look-up of the second field within ONLY the records already selected by the first field, followed by rapid look-up of the third field - again, only within the records selected by the previous two indices.

Is that the correct reason why the first is not needed? This would be expanded out dependent on the # of columns?