Re: key = currval('tab_key_seq') choses SEQSCAN?!

Brandon Craig Rhodes <brandon@oit.gatech.edu> writes:
> But this same table suddenly becomes unwilling to use an index scan if
> the target value is the result of the currval() function:

currval() is considered a volatile function, therefore it is unsafe to
use in an indexscan constraint.

The subselect hack mentioned nearby fools the planner ... at the moment.
I wouldn't guarantee that it will work indefinitely.  A better solution
is to wrap currval() in a function that you lyingly claim is stable.

            regards, tom lane