LOAD 'pg_savior';
CREATE EXTENSION IF NOT EXISTS pg_savior;
NOTICE:  extension "pg_savior" already exists, skipping
CREATE TABLE emp (id int);
INSERT INTO emp VALUES (1), (2), (3);
-- UPDATE without WHERE: must error, table unchanged
UPDATE emp SET id = 99;
ERROR:  pg_savior: UPDATE without WHERE clause is blocked
HINT:  Add a WHERE clause, or set pg_savior.bypass = on for this session.
SELECT count(*) AS still_one FROM emp WHERE id = 1;
 still_one 
-----------
         1
(1 row)

SELECT count(*) AS none_yet  FROM emp WHERE id = 99;
 none_yet 
----------
        0
(1 row)

-- UPDATE with WHERE: succeeds
UPDATE emp SET id = 99 WHERE id = 1;
SELECT count(*) AS gone_now  FROM emp WHERE id = 1;
 gone_now 
----------
        0
(1 row)

SELECT count(*) AS one_now   FROM emp WHERE id = 99;
 one_now 
---------
       1
(1 row)

DROP TABLE emp;