Re: Saving loading time at counting rows

Joep Roebroek wrote:

I had this question, which I didn't really know where to ask, so I thought to begin at this mailing list. Very basicly said, I count the rows of a table which had approx 50000 or more rows. The problem is, there is a notable difference in loading time with other pages. Is there a technique to estimate the number of rows instead of exactly couting them? So that it saves loading time. For example, when you search with google, you get an estimate of the number of results, how do they do this? Maybe this is not a question for the PHP Mailing list, but if not where is a better place to ask this?

Sadly you didn't say which database you are using... so I'll give you an answer for MySQL... I don't know what other DBs do. Say you have: SELECT * FROM table WHERE condition; You only show the n results but these may be "paged" or offset. What I would do here is: SELECT SQL_CALC_FOUND_ROWS * FROM table WHERE condition LIMIT n OFFSET y; This limits how many results MySQL actually gives you *but* allows you to know what the full number of results would have been if you hadn't used LIMIT via a second statement: SELECT FOUND_ROWS() Hopefully that solves your issue, but perhaps I've missed what you are actually trying to do. Col Is that the kind of answer you are looking for?