[gnome-db] Re: Thank you for this marvelous work



> And, what are the strict/not-strict functions?

http://www.postgresql.org/idocs/index.php?sql-createfunction.html
The following items may appear in the WITH clause:

iscachable
Iscachable indicates that the function always returns the same result 
when given the same argument values (i.e., it does not do database lookups or 
otherwise use information not directly present in its parameter list). The 
optimizer uses iscachable to know whether it is safe to pre-evaluate a call 
of the function.
isstrict

isstrict indicates that the function always returns NULL whenever any of 
its arguments are NULL. If this attribute is specified, the function is not 
executed when there are NULL arguments; instead a NULL result is assumed 
automatically. When isstrict is not specified, the function will be called 
for NULL inputs. It is then the function author's responsibility to check for 
NULLs if necessary and respond appropriately.

******
Cheers,
Jean-Michel POURE



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