Kurt Welgehausen wrote:
Currently, indices are not used to look up either term
in an OR expression.
See <http://www.sqlite.org/php2004/page-052.html>.
You could build 2 separate 5-column indices and use a
union.
Regards
his is not true. databases split usually queries into several sub
queres, if you use an OR clause in the middle of indexed fields. I don't
know, if sqlite is doing somelike things.
As example, imagine you have two fields in an index (field1, field2)
select field1, field2 where field1 = 'value' and (field2 = 'value1' or
field2 = 'value2')
the database will start two subqueris and make a unique union of both
results:
select field1, field2 where field1 = 'value' and field2 = 'value1'
select field1, field2 where field1 = 'value' and field2 = 'value2'
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