Hi, I need to sum up the elements of two arrays. Most arrays were of the same size, thus I just unnested the arrays in one table and grouped the results in a loop for every row. When two arrays of different size (1200 and 1300) were processed, the memory usage exploded and the query was killed by the kernel.
As I now understand, the following query leads to 12 results, not just 4 (or 3...): SELECT unnest(ARRAY[1,2,3]), unnest(ARRAY[4,5,6,7]); Why could postgres use as much memory till the kernel complained when unnesting 1200 and 1300 elements resulting in 1.6e6 rows. Are there settings to prevent this such as "work_mem"? Regards, Andreas ___________________________________________________________________________ SCANLAB AG Dr. Andreas Simon Gaab Entwicklung * R & D Siemensstr. 2a * 82178 Puchheim * Germany Tel. +49 (89) 800 746-513 * Fax +49 (89) 800 746-199 mailto:a.g...@scanlab.de * www.scanlab.de<http://www.scanlab.de> Amtsgericht München: HRB 124707 * USt-IdNr.: DE 129 456 351 Vorstand: Georg Hofner (Sprecher), Christian Huttenloher, Norbert Petschik Aufsichtsrat (Vorsitz): Dr. Hans J. Langer ___________________________________________________________________________ Besuchen Sie uns auf der / Meet us at LASER World of PHOTONICS 2011 Munich, Germany May 23 - 26, 2011 Hall C2, Booth 461
