Just to clarify something here. The 'limit' clause has no effect on the efficiency of the search. It affects the overall efficiency of the query because it prevents you from accidentally requesting more rows than you can handle.

In the case where there is a unique index on the field (which is essentially what a PK-identity is anyway) the limit is entirely superlfuous and probably actually slows things down just marginally as its more to be marshalled accross the interprocess or intermachine barrier. Also to the best of my knowledge 'limit' is not standard SQL but rather a MySQL extension.

Anyway. ;-)


---
demerphq

    First they ignore you, then they laugh at you, then they fight you, then you win.
    -- Gandhi

    Flux8


In reply to Re^2: Ranking position in a SQL index by demerphq
in thread Ranking position in a SQL index by Anonymous Monk

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