Thanks Rabbit, I fixed by adding primary key for the second table,fileConne ction and by change my index field from 'file_id' to 'parent_id'.

I can not able to see the following query result. start running before 10 hrs. I try to fix the problem by adding index for both tables I used and also I enabled mysql query catch. For your information

I used mac os X, processor 2.66 GHz intel core I7, 4 GB memory 1067 MHz DDRS. and mysql version : 5.5.14;

number of records in fileinfo : 495,557 and fileConnection: 6,298,732.

create table SelectedFileLin ksChilds...