| deltab | mDuff: types.FunctionType |
| mDuff | ahh; graci |
| hays | roygbiv: the queries are so simple.. its like SELECT * FROM foo WHERE x='bar' AND y='baz'; |
| roygbiv | e.g. cross product joins, indexed or not, can really grind a system when you have 50 million rows ;) |
| deltab | or type(lambda: None) |
| action | mDuff obviously didn't look hard enough before coming here; sorry 'bout that. |
| mDuff | obviously didn't look hard enough before coming here; sorry 'bout that. |
| hays | roygbiv: no joins.. its just a flat database |
| roygbiv | i don't know. check ulimit? make sure your not being choked by OS constraints |
| mDuff | hays: what you're describing is certainly not consistent with my experience w/ postgres. |
| hays | roygbiv: now x is indexed and y is indexed, but I don't bother to index (x,y) I wonder if they run on the same port hmm |
| kosh | you would want to ask the postgres planner how it was going to do the query that should tell you where the problems are |
| roygbiv | yep the PG query planner is nice but maybe not of much help on a simple single table select |
| kosh | it would tell if your query was written in such a way as to cause postgres to do a sequential table scan so you could find out about problems |
| roygbiv | kosh but he says he has fully indexed queries and it's still taking 2 seconds |
| kosh | he has the fields indexed that does not mean that the db is using those indexes that is why you need to ask the query planner |
| hays | i would hope so |
| kosh | depending on how you word a query a db can decide it is more efficient to do a linear scan instead of using an index that is why you would want to see the plan |
| roygbiv | well you're right, there could be some value to using the query planner. give it a try hays. might learn something interesting there... |
| kosh | trying to predict what the db will do is usually a bad idea I have had times where I figured that it should use indexes when it did not and there are ways to force it and the db turned out to be right, it did run slower using the indexes so guessing is a bad move, just ask the db what it is doing |
| hays | http://rafb.net/p/3umVsF21.html <-- does this tell you guys anything? (MySQL) |
| kosh | that seems to say it is using an index scan and only checking 225 rows |
| roygbiv | hays, not much ;) as expected. it's only 225 rows? |
| kosh | at least that is my reading |
| hays | that query takes 9 seconds |
| sinkaos | I have an array class member. I want to only strings or objects of a particular type in that array. How do I arrange the class to ensure this? |
| hays | 225 rows are the output, I believe, there are many many rows in the whole table |
| Jerub | sinkaos: uh, you're not making any semse. sinkaos: no one uses arrays in python. |
| sinkaos | Lists, whatever. |