I am using the following delete statement.
delete /*+ parallel(t,30) */ from master_header t;
Sometimes the degree 30 is not working.
On what basis we have to give the degree.
Is the degree is session specific?
To use this hint we need to follow any guidelines or check list.
Please help me.
It would be nice to know the database version you're working with, the number of CPU's and so on...
But at least you can read about it here:
and the respective links mentioned in those articles.
does your system have the capacity to have multiple parallel queries with 30 processes running concurrently? (like a Sun 6900 with 48-dual core processors or something. A little 8cpu box will not be able to handle this. That is why it is called a "hint". While you can "hint" in a query, the CBO can (and in this case will) ignore it and will reduce the parallel degree to what it sees the system can handle. It tries to keep developers from doing stupid stuff.