Re: Perplexed by reverse SELECT statement.

[Bruce Feist]

Tore Bostrup wrote:

I'm sure you are aware that this is a non-normalized database design, and
that those tend to make designing queries more difficult and/or inefficient.
The LIKE operator should give you what you want, but you need to be careful:

(PHP string def:)

$sSQL = "SELECT <list>
FROM <table>
WHERE readBy LIKE '$UserID,%'
OR readBy LIKE '%,$UserID'
OR readBy LIKE '%,$UserID,%'"
You need to look for the three situations to avoid matching the wrong
entries in for example (11,20) (5,11) or (5,11,20).
 

You left one out.

OR readby = '$UserID'

to cover the case where there's only one reader.  Other than that, I agree.

Bruce Feist



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