Optimise two mysql queries to one query

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Optimise two mysql queries to one query

Optimise two mysql queries to one query

2004-03-16 - By Sasha Pachev

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Reply: 1 2

dr zoidberg wrote:
> Hello,
>
> $a = mysql_query( "Select a,b FROM t WHERE category=1 ")
> while($a) {
> $x = $a[a];
> //some echo
> //another query
>
> $b = mysql_query( "Select * FROM t WHERE subcategory=$x ")
> while ($b) {
> //some echo
> }
> }

Not tested and might need some tweaking in the where clause, but should be at
least close to what you need:

select t2.* from t t1, t t2 where t1.category=1 and t2.subcategory = t1.a

--
Sasha Pachev
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