MySQL incorrect key file for tmp table when making multiple joins

Question

I don\'t come here for help often but I am pretty frustrated by this and I am hoping someone has encountered it before.

Whenever I try to fetch records from a table

Answer 1

On Unix, MySQL uses the value of the TMPDIR environment variable as the path name of the directory in which to store temporary files. If TMPDIR is not set, MySQL uses the system default, which is usually /tmp, /var/tmp, or /usr/tmp.

On Windows, Netware and OS2, MySQL checks in order the values of the TMPDIR, TEMP, and TMP environment variables. For the first one found to be set, MySQL uses it and does not check those remaining. If none of TMPDIR, TEMP, or TMP are set, MySQL uses the Windows system default, which is usually C:\windows\temp.

If the file system containing your temporary file directory is too small, you can use the --tmpdir option to mysqld to specify a directory in a file system where you have enough space.

In MySQL 5.0, the --tmpdir option can be set to a list of several paths that are used in round-robin fashion. Paths should be separated by colon characters (“:”) on Unix and semicolon characters (“;”) on Windows, NetWare, and OS/2.