That doesnt seem to be a large document at all. Has the server run out of memory?
The only thing is that you have 21 tables all connected which is unusual. As an experiment, try joining some of the tables together to combine their data and reduce the number of tables/links that Qlikview has to manage.
I tried to join tables using outer join so that all data must be there and no record from master or fact table will be removed, but same out of memory problem exists. That's make to think this is due to unwanted services. There is 3 GB ram in server. There is one more thing out of 3 large tables 1 is replica of employee ( master table ) this table is used to link employee with allocation. Is it possible due to repetation of records in these 2 tables system getting hanged.
I still think that the problem is not in data model. And, the number of records is really small to cause any problem. What's your qvw files size? Most likely something is wrong with your front-end objects. Try to remove them. I'm not talking about selections - just delete your front end charts/tables and see if it changes anything.
As i said this is begening of application. No charts or front end objects exists. On 1'st sheet itself if i add three table box this warning is shown. This made me to believe that server is also hosted on this machine and there is an application hosted might taking enough ram or logical space. What u say, is it possible?
Obviously I have not seen your data model, but "out of memory" and "outer join" sort of jumped out at me (especially if outer join means full outer join).
Remember that an outer join can significantly increase the size of the data. If you have two tables of 3 million records each that overlap on only 1 record, your result set will have 6 million (minus 1) records. If they overlap on none, you could get a cartesian join and land up with 9 000 billion records.
I suggest that you try selectively commenting out part of the load script to reduce the model until it loads OK. Then add back the script (excluding the last bit you commented out) one step at a time and confirm that everything loads OK, when it fails you have found the problem (or at least part of it).
Logic will get you from a to b. Imagination will take you everywhere. - A Einstein