Hello all,
Here a simple issue I have with performance : 1/ I create a table A and populate it with a bulk load 2/I create a table B, I populate the table with bulk load
3/I create table C with a CTAS statement. I analyze the statistics and set the primary key
4/I try a "count distinct" type query (on all the table) on the PK Field. It is pretty slow, with a high sollicitation of my hard drive for several dozens of second. the "select count" is however fast.
So I have these following questions : 1/why despite statistics the count distinct query is slow? I thought the idea of statistics was to get some metrics about the table? 2/if the field I make a count distinct on is the PK (or the set of field is the PK), it's exactly the same than a count non null. So why the time are not the same? 3/if these issues are design issue or bugs, how can I ask to make it solved?
For information : Monetdb 11.31.13 on Windows 10
Best regards,
Simon AUBERT [cid:691B9F4089B9F34B8E0C22B39B7117EC@eurprd07.prod.outlook.com] Bourse Maritime - 1, place Lainé - 33 000 Bordeaux Mob : +33(0)6 66 28 52 04
