I am having a strange problem with a query... I have a table that contains 3 columns and 3,315,599 rows. One of the columns is a date time field. Out of 3,315,599 rows 1,555,157 contain an entry in the date time field and the other 1,760,442 rows contain null in the date time field.... Here is the problem I will illustrate it with queries and results.
Illustrates the number of rows in the table mysql> select count(compid) from dbLastFaxed ; +---------------+ | count(compid) | +---------------+ | 3315599 | +---------------+ 1 row in set (0.00 sec) illustrates the number of rows with dates in the lastFaxedDateTime field mysql> select count(compid) from dbLastFaxed where lastFaxedDateTime < '2001-12-01 00:00' ; +---------------+ | count(compid) | +---------------+ | 1555157 | +---------------+ 1 row in set (7.84 sec) illustrates the number of rows with a null value in the lastFaxedDateTime field mysql> select count(compid) from dbLastFaxed where lastFaxedDateTime = null ; +---------------+ | count(compid) | +---------------+ | 1760442 | +---------------+ 1 row in set (11.05 sec) Huh? Shouldn't this query yield 3,315,599 (1,555,157+1,760,442) Whats going on here? mysql> select count(compid) from dbLastFaxed where lastFaxedDateTime < '2001-12-01 00:00' or lastFaxedDateTime =null; +---------------+ | count(compid) | +---------------+ | 1555157 | +---------------+ 1 row in set (8.29 sec) --------------------------------------------------------------------- Before posting, please check: http://www.mysql.com/manual.php (the manual) http://lists.mysql.com/ (the list archive) To request this thread, e-mail <[EMAIL PROTECTED]> To unsubscribe, e-mail <[EMAIL PROTECTED]> Trouble unsubscribing? Try: http://lists.mysql.com/php/unsubscribe.php
