Hello. Apologies if this is not the right place to bug report extensions, but I couldn’t find a better place. An at the very least I’d like to save someone a day of debugging this issue.
The isn_weak function in the isn extension reports the wrong value if you look at it inside a transaction:
BEGIN;
-- Prepare a statement for isn_weak(): PREPARE s_1 AS SELECT isn_weak() AS prepared_check;
-- First check - locks in the isn_weak value EXECUTE s_1; -- => FALSE
-- Set isn_weak(true): SELECT isn_weak(true) AS setting_true;
-- Check using normal query: SELECT isn_weak() AS direct_check; -- => TRUE
EXECUTE s_1; -- => FALSE (!!!!)
This is because by default, that function is marked as immutable:
d6kpcv43m9du6> \df+ isn_weak List of functions ─[ RECORD 1 ]───────┬────────────────── Schema │ public Name │ isn_weak Result data type │ boolean Argument data types │ Type │ func Volatility │ immutable <————— bad Parallel │ restricted Owner │ postgres Security │ invoker Access privileges │ Language │ c Internal name │ weak_input_status
I can manually fix this by changing it to STABLE:
ALTER FUNCTION isn_weak() STABLE;
Am I missing something or isn’t this quite weird? Would it at least be possible to change the documentation to explain this?
