Re: [HACKERS] query execution question

2011-02-09 Thread Kevin Grittner
amit sehas wrote: > We are making some performance measurements, we are trying to > determine query execution behavior. I hope you're not doing this on an un-tuned server or "toy" tables. There are a number of configuration parameters which should be tuned for your particular server, which wi

Re: [HACKERS] query execution question

2011-02-09 Thread Nicolas Barbier
2011/2/9 amit sehas : > Lets say that the cost based optimizer determines that the order of the > joins should be   T1.a=T2.b followed by T2.c = T3.d followed by T3.e = T4.f > > the question we have is during query execution are the joins evaluated > completely one by one in that order, or the fir

[HACKERS] query execution question

2011-02-09 Thread amit sehas
We are making some performance measurements, we are trying to determine query execution behavior. Lets say we have 4 tables T1, T2, T3 and T4 and the query has the form: select * from T1, T2, T3, T4 where (T1.a = T2.b and T2.c = T3.d T3.e = T4.f) where a,b,c,d,e,f are properties of the re