Your first query returns a scalar (single value), right? You can put its value into a variable, and use that in the second query. It's not exactly what you wanted, but it will work without external programming.
Regards, Jerry Schwartz Global Information Incorporated 195 Farmington Ave. Farmington, CT 06032 860.674.8796 / FAX: 860.674.8341 -----Original Message----- From: Xiaobo Chen [mailto:[EMAIL PROTECTED] Sent: Tuesday, September 26, 2006 10:09 AM To: [EMAIL PROTECTED] Cc: mysql@lists.mysql.com Subject: Re: Help for query I found if I divided into 2 steps, I will find the record in table B: Ta - the given timestamp from table A; 1) select min(abs(Ta - timestamp)) as min_t from B; 2) select * from B where (timestamp + min_t = Ta) or (timestamp - min_t = Ta); But, how can I make these 2 steps into 1 query? Thanks. Xiaobo > Hi, all > > The version of Mysql is 4.0.15 on Solaris 9. I am in such a situation. > There are 2 tables something like these: > > Table A: > ---------------------------------- > location|timestamp | other fields > ------------------------------- > > > Table B > > -------------------------------- > location|timestamp | other fields > --------------------------------- > > (location. timestamp) make the 'primary key' for each table. > > The task is that: the locations are the same, given a timestamp from table > A, I need to find the record in table B which has the closest timestamp as > the given one in table A. > > I checked the book and research the internet, but didn't find a hint or > solution yet. Could any one give me a hint please? > > Thanks in advance. > > Xiaobo > > > -- > MySQL General Mailing List > For list archives: http://lists.mysql.com/mysql > To unsubscribe: http://lists.mysql.com/[EMAIL PROTECTED] > > -- MySQL General Mailing List For list archives: http://lists.mysql.com/mysql To unsubscribe: http://lists.mysql.com/[EMAIL PROTECTED] -- MySQL General Mailing List For list archives: http://lists.mysql.com/mysql To unsubscribe: http://lists.mysql.com/[EMAIL PROTECTED]
