----- Original Message ----- From: "Mojtaba Faridzad" <[EMAIL PROTECTED]> To: <[EMAIL PROTECTED]> Sent: Tuesday, July 22, 2003 4:40 PM Subject: Re: how to limit COUNT(*)
> for example: > > SELECT COUNT(*) as numfound FROM mytable WHERE mycondition; > > in this query, mytable and mycondition are variable and on run time, they > are changed. I use this query to jump to the last page of a grid form. > sometimes the query may have more than million records and I want to give a > warning to the user to specify a condition to limit the number of records. I > would like to count the records upto 10000 (for example) and if the records > are more than this, stop counting and ask user to change the condition. to > solve this problem I did something like this: > > SELECT one_field FROM mytable WHERE mycondition LIMIT 10001; > > if the number of records of this query is equal to 10001, then I show the > warning message. but this query is not as fast of COUNT query. is there any > way to limit the first query? > I dunno if I understood your problem. But if you want to *limit the count()* try to put a condition after fetching the result. if( count_result > MAX_NO) then count_result = MAX_NO; If you want to paginate your result try use LIMIT v1, v2 [look in manual for more information about SELECT & LIMIT] If you just want to view the last info rows try to order desc over an auto_increment field. good luck > thanks > > ----- Original Message ----- > From: "gerald_clark" <[EMAIL PROTECTED]> > To: "Mojtaba Faridzad" <[EMAIL PROTECTED]> > Cc: <[EMAIL PROTECTED]> > Sent: Tuesday, July 22, 2003 9:15 AM > Subject: Re: how to limit COUNT(*) > > > > Perhaps you could post some examples of what you have tried. > > I don't understand what you are asking. > > > > Mojtaba Faridzad wrote: > > > > >Hi, > > > > > >I guess there is no way to limit COUNT(*). Is that right? We cannot use > the > > >result of COUNT in WHERE condition or LIMIT doesn't help. In this case so > > >far I have retrieved a field and used LIMIT. Is there a better way to > > >control it? > > > > > >Thanks > > > > > > > > > > > > > > > > > > > > -- > > 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]
