We jumped from 3.23 to 5 and back again in the space of a month and a half. We tried 4.1 in December 2005 with the same results, the server was VERY slow and it had a big impact on our business.
The query locks the tables that it is working on. I look at the database through MySQL administrator and I can see that the users connection that runs this query is selectting but all the other connections is “locked” in status. This stops the users from accessing the data.
A bit of background info on the server and type of applications running on this server. The db server is accessed by ± 50 users on the local network with a program developed in C++. Intranet user also access the same server and databases with internet applications wrote is .net/asp. The problem comes in when the Intranet users access the same database that the C++ users access