SELECT id from tree_field_index 
  WHERE ( (field='usage' AND name='cider') 
  OR      (field='usage' AND name='juicer') ) 
  AND     (field='flowering' AND name='spring') 
  AND     (field='ripe' AND name='autumn')

[download]

This won't work. The select statement gets applied to each record in turn.You can't have a single record where field='usage' AND field='flowering' so the result will be nothing.

Which database are you using, and how many records roughly are you dealing with ?

poj

In reply to Re^3: OT - SQL choosing a schema for index tables by poj
in thread OT - SQL choosing a schema for index tables by bangor

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