Also i see there is no need for the selecting all id column of all the child tables:

select a.dtimesheetid,b.dtimesheetid,c.dtimesheetid, d.dtimesheetid,e.dtimesheetid,f.dtimesheetid

since a.dtimesheetid = b.dtimesheetid, both are same in the output.

Also, a.dtimesheetid = c.dtimesheetid, then both are same.

So, instead of writing

select a.dtimesheetid,b.dtimesheetid,c.dtimesheetid, d.dtimesheetid,e.dtimesheetid,f.dtimesheetid

you can write like

select DISTINCT a.dtimesheetid

FROM

......

Hope this helped you.