Is there a way to make a query more efficient by executing a sub-select
only once? In a query such as: SELECT a, (select b from c where d = e limit 1), npoints( (select b from c where d = e limit 1) ) FROM f WHERE isValid( (select b from c where d = e limit 1) ); I do the same sub-select 3 times in the query. I tried the following: SELECT a, (select b from c where d = e limit 1) AS g, npoints( g ) FROM f WHERE isValid( g ); But this gave an error regarding "column 'g' does not exist". How can I avoid making the same sub-select 3 times? Mark |
begin:vcard fn:Mark Fenbers n:Fenbers;Mark org:DoC/NOAA/NWS/OHRFC adr:;;1901 South SR 134;Wilmington;OH;45177-9708;USA email;internet:[EMAIL PROTECTED] title:Sr. HAS Meteorologist tel;work:937-383-0430 x246 x-mozilla-html:TRUE url:http://weather.gov/ohrfc version:2.1 end:vcard
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