Thread: Mail about select
Dear Friends, I have two tables 1. "Radius" Table = radius +----------------------------------+----------------------------------+-------+ | Field | Type | Length| +----------------------------------+----------------------------------+-------+ | uname | char() | 256 | | logdate | date | 4 | | logtime | time | 8 | | duration | int4 | 4 | | status | char() | 20 | | nasadd | char() | 20 | | port | int4 | 4 | | bytesin | int4 | 4 | | bytesout | int4 | 4 | | packin | int4 | 4 | | packout | int4 | 4 | | misc | int4 | 4 | +----------------------------------+--------------------------------- 2) "radiustemp" with the same structure now i am firing a query like this: select r.uname from radius r, radiustemp rt where r.uname<>rt.uname and r.logdate<>rt.logdate and r.logtime<>rt.logtime; After some time i get response "Segmentation Error" core(sumped) can any one help what is the error in this query. Thanks in advance for your kind help. Regards, Vikrant
Vikrant Rathore <vikrant@chemquick.com> writes: > now i am firing a query like this: > select r.uname from radius r, radiustemp rt where r.uname<>rt.uname and > r.logdate<>rt.logdate and r.logtime<>rt.logtime; > After some time i get response > "Segmentation Error" > core(sumped) How big are your tables? That query will probably produce an output row for almost every combination of a row from radius with a row from radiustemp, which might overflow the allowed memory for your application. I suppose what you really want is to find the rows in radius that do not have duplicates in radiustemp, but that query won't do it... regards, tom lane