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Re: SQL optimization - WHERE SomeField STARTING WITH ...

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Bill wrote:
Tino Wildenhain wrote:
Hi Bill,

Bill wrote:
The SQL database servers I have worked with cannot use and index for a SELECT of the form

SELECT * FROM ATABLE
WHERE AFIELD LIKE ?

because there is no way to know the location of the wild card until the parameter value is known. InterBase and Firebird allow

SELECT * FROM ATABLE
WHERE AFIELD STARTING WITH ?

which is equivalent to LIKE 'ABC%' and will use an index on AFIELD. Is there a similar syntax in PostgreSQL?

Yes, its actually: LIKE 'ABC%' and it will use an index.

Regards
Tino
Are you saying that a parameterized query whose WHERE clause is AFIELD LIKE ? will use an index on AFIELD if the parameter value is 'ABC%'. I
...
no, I'm not saying that anymore (nor did I intend to do :-) I was just
misreading your question. Sorry.

Regards
Tino

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