Re: [HACKERS] Postgres 6.5 beta2 and beta3 problem

> LIKE doesn't know anything about indexes, nor vice versa.  What the
> index-scan machinery *does* know about is <, <=, etc.  If you have
> WHERE clauses like "x >= 33" and "x <= 54" then an index scan knows
> to only scan the part of the index from 33 to 54.  So you never even
> visit a large fraction of the table.  This is why an index scan can
> be faster than a sequential scan even though the per-tuple overhead
> of consulting the index is larger.
> 

You know, everyone beats me up for that LIKE indexing hack, but every
month that goes by where someone does not come up with a better solution
makes me feel a little better about the criticism.

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