No body has answered my question so far. Does that mean there is no way to retrieve current row numbers in a query or no way to retrieve results jumping steps?
I would appreciate any help. Thanks, Joao. -----Mensagem encaminhada----- > From: Joćo Borsoi Soares <[EMAIL PROTECTED]> > To: [EMAIL PROTECTED] <[EMAIL PROTECTED]> > Subject: row numbers, jumping rows > Date: Sun, 21 Nov 2004 11:23:41 -0200 > > Hello list, > > I wonder if someone could help me to get the fastest result on my query. > I need to classify one entity, according to a specific attribute (let's > call it X), looking at a sample extracted from a database table. > First I need to sort my sample ordered by a specific table field (X). > Then I should divide my sorted sample in 10 equal groups (same number of > rows). Finally, I should classify my entity (1 to 10), finding out at > which group its attribute X fits in. > > Let me explain my thoughts. First I should make a "SELECT COUNT(*).." to > find the total number of rows in my sample. Then I make queries using > LIMIT until I find which group the X attribute fits in. In the worst > case I will have to do 10 queries. Which I think should take too long in > my case. > > I wanted to make it in only one query. It could be possible if I could > make a query which returns result jumping rows, like "STEP N" where "N" > could be the number of items in each group. Is there anything in mysql > that can give me that? I also thought if I could have the row numbers in > the query result, I could solve it with a simple condition like, "WHERE > rowNum % N = 0". > > Any ideas? > > Thanks. > > > -- MySQL General Mailing List For list archives: http://lists.mysql.com/mysql To unsubscribe: http://lists.mysql.com/[EMAIL PROTECTED]
