1CREATE EXTENSION lo; 2CREATE TABLE image (title text, raster lo); 3CREATE TRIGGER t_raster BEFORE UPDATE OR DELETE ON image 4 FOR EACH ROW EXECUTE PROCEDURE lo_manage(raster); 5SELECT lo_create(43213); 6 lo_create 7----------- 8 43213 9(1 row) 10 11SELECT lo_create(43214); 12 lo_create 13----------- 14 43214 15(1 row) 16 17INSERT INTO image (title, raster) VALUES ('beautiful image', 43213); 18SELECT lo_get(43213); 19 lo_get 20-------- 21 \x 22(1 row) 23 24SELECT lo_get(43214); 25 lo_get 26-------- 27 \x 28(1 row) 29 30UPDATE image SET raster = 43214 WHERE title = 'beautiful image'; 31SELECT lo_get(43213); 32ERROR: large object 43213 does not exist 33SELECT lo_get(43214); 34 lo_get 35-------- 36 \x 37(1 row) 38 39-- test updating of unrelated column 40UPDATE image SET title = 'beautiful picture' WHERE title = 'beautiful image'; 41SELECT lo_get(43214); 42 lo_get 43-------- 44 \x 45(1 row) 46 47DELETE FROM image; 48SELECT lo_get(43214); 49ERROR: large object 43214 does not exist 50DROP TABLE image; 51