----- Original Message ----- From: "Martin Rytz" <[EMAIL PROTECTED]> To: <[EMAIL PROTECTED]> Sent: Wednesday, November 24, 2004 8:47 AM Subject: Multiple table count in one sql-query
> Hello People > > I should have the count from 3 tables in one query; something like this: > > select count(*) from table1 union select count(*) from table2 union select > count(*) from table3 union; > > The Problem ist, that the query gives 3 results back (the count from table1, > table2 and table3) BUT I should have only one result, the added value from > all 3 tables... > > How can I do this within MySQL? Are there variables I could use within the > query? Other possibilities? > > Thank you for your help! > One approach would be to create a temporary table consisting of one integer column, then write the results of your query to that table. Here is a script that demonstrates this technique: #Create temporary table containing a union of the row counts from each of severa create temporary table if not exists temp01 select count(*) as total_rows from Employee UNION select count(*) as total_rows from emp UNION select count(*) as total_rows from dept; #Display the contents of the temporary table. select * from temp01; #Sum the row counts from the different tables. select sum(total_rows) from temp01; #Drop the temporary table. drop table if exists temp01; This script works perfectly on my 4.0.15 system. Rhino -- MySQL General Mailing List For list archives: http://lists.mysql.com/mysql To unsubscribe: http://lists.mysql.com/[EMAIL PROTECTED]
