Hello,
this proposal change older unaccepted proposal
http://archives.postgresql.org/pgsql-hackers/2006-03/msg01157.php .
Changes:
* based on prepared statements
* syntax and behave is near to Oracle
* usable as protection from SQL injection
New syntax:
a) EXECUTE stringexpr [INTO [STRICT] varlist [USING exprlist]
b) FOR varlist IN EXECUTE stringexpr USING exprlist LOOP ....
Reason:
* defence from SQL injection
* more readable, shorter, more comfortable
Sample (secure dynamic statement):
EXECUTE 'SELECT * FROM ' || CASE tblname WHEN 'tab1' THEN
'tab1' WHEN 'tab2' THEN 'tab2' ELSE '"some is wrong"' END ||
' WHERE c1 = $1 AND c2 = $2' USING unsecure_parameter1, unsecure_parameter2;
Difference between PL/SQL and proposal:
* allow only IN variables
* use PostgreSQL placeholders notation - "$"n instead ":"n
Compliance with PL/SQL
* You can use numeric, character, and string literals as bind arguments
* You cannot use bind arguments to pass the names of schema objects to
a dynamic SQL statement.
Best regards
Pavel Stehule