ORDER BY causing disk space error

[empiresolutions]

The following query is causing a mysql error The Error number is 28, which means low disk space. So I clear some space, retry and get the error again after a few times querying. After playing with query i find that the ORDER BY statement is what make it fail. If i remove it the script runs.

So my question is, is there something about an ORDER BY statement that takes up a lot of disk space? I can sort in PHP, but if MySQL has the ability then i prefer it to sort with.

Thanks for all the suggestions.

SELECT data.datasize AS size, data.dataid AS id, data.datatype, data.dataname, data.datadescription AS description, data.engineerid AS owner, datalog.usability AS usability,datalog.easeofdownload AS easeofdownload, datalog.docaccuracy AS accuracy, datalog.timesdownloaded AS timesd, datalog.ratings AS ratings from data, datalog where data.datatype = 'AE Training video' AND data.dataid = datalog.dataid ORDER BY data.dataname

[ronverdonk]

You can prefix your statement with EXPLAIN so you can check whether MySQL can use indexes to resolve the query. It cannot if you see Using filesort in the Extra column.

Do you have an index on data.dataname ? If not, try that.

Ronald