[SQL] Join or Where?

[Együd Csaba]

Title: Urgent Help : Use of return from function/procedure.

Hi, could anybody tell me what can be the difference between these queries? There are a big difference but I can't understand the reasons. For some reasons the firs query calculates getup column in a wrong way. It allways devides with 10. (???) While the getupquantity column comes well. With the second query everything is ok. Thank you, -- Csaba ---------------------------------------------------------------------------- ------- select (select getupquantity from t_products where id=productid) as getupquantity,        quantity,        (select quantity/getupquantity) as getup from t_stockchanges, t_products where (getupquantity<>0) limit 30; RESULT:  getupquantity | quantity | getup ---------------+----------+-------             10 |      100 |    10             10 |    10600 |  1060             15 |    15150 |  1515             13 |    13650 |  1365           17.5 |    17500 |  1750           5.75 |     5750 |   575            2.5 |     2500 |   250            1.5 |     1500 |   150             16 |    16000 |  1600              2 |     2000 |   200            5.5 |     5500 |   550            4.5 |     4500 |   450              2 |     2000 |   200 ---------------------------------------------------------------------------- ------- select t_products.getupquantity as getupquantity,        quantity,        (select t_stockchanges.quantity/t_products.getupquantity) as getup from t_stockchanges join t_products on (t_products.id=productid) where (getupquantity<>0) limit 30; RESULT: getupquantity | quantity | getup ---------------+----------+-------             10 |      100 |    10             10 |    10600 |  1060             15 |    15150 |  1010             13 |    13650 |  1050           17.5 |    17500 |  1000           5.75 |     5750 |  1000            2.5 |     2500 |  1000            1.5 |     1500 |  1000             16 |    16000 |  1000              2 |     2000 |  1000            5.5 |     5500 |  1000            4.5 |     4500 |  1000              2 |     2000 |  1000 -------------------------------------------------------------------- Hi, could anybody tell me what can be the difference between these queries? There are a big difference but I can't understand the reasons. For some reasons the firs query calculates getup column in a wrong way. It allways devides with 10. (???) While the getupquantity column comes well. With the second query everything is ok. Thank you, -- Csaba ---------------------------------------------------------------------------- ------- select (select getupquantity from t_products where id=productid) as getupquantity,        quantity,        (select quantity/getupquantity) as getup from t_stockchanges, t_products where (getupquantity<>0) limit 30; RESULT:  getupquantity | quantity | getup ---------------+----------+-------             10 |      100 |    10             10 |    10600 |  1060             15 |    15150 |  1515             13 |    13650 |  1365           17.5 |    17500 |  1750           5.75 |     5750 |   575            2.5 |     2500 |   250            1.5 |     1500 |   150             16 |    16000 |  1600              2 |     2000 |   200            5.5 |     5500 |   550            4.5 |     4500 |   450              2 |     2000 |   200 ---------------------------------------------------------------------------- ------- select t_products.getupquantity as getupquantity,        quantity,        (select t_stockchanges.quantity/t_products.getupquantity) as getup from t_stockchanges join t_products on (t_products.id=productid) where (getupquantity<>0) limit 30; RESULT: getupquantity | quantity | getup ---------------+----------+-------             10 |      100 |    10             10 |    10600 |  1060             15 |    15150 |  1010             13 |    13650 |  1050           17.5 |    17500 |  1000           5.75 |     5750 |  1000            2.5 |     2500 |  1000            1.5 |     1500 |  1000             16 |    16000 |  1000              2 |     2000 |  1000            5.5 |     5500 |  1000            4.5 |     4500 |  1000              2 |     2000 |  1000 --------------------------------------------------------------------