51 lines
940 B
Plaintext
51 lines
940 B
Plaintext
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CREATE EXTENSION lo;
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CREATE TABLE image (title text, raster lo);
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CREATE TRIGGER t_raster BEFORE UPDATE OR DELETE ON image
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FOR EACH ROW EXECUTE PROCEDURE lo_manage(raster);
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SELECT lo_create(43213);
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lo_create
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-----------
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43213
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(1 row)
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SELECT lo_create(43214);
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lo_create
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-----------
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43214
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(1 row)
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INSERT INTO image (title, raster) VALUES ('beautiful image', 43213);
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SELECT lo_get(43213);
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lo_get
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--------
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\x
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(1 row)
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SELECT lo_get(43214);
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lo_get
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--------
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\x
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(1 row)
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UPDATE image SET raster = 43214 WHERE title = 'beautiful image';
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SELECT lo_get(43213);
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ERROR: large object 43213 does not exist
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SELECT lo_get(43214);
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lo_get
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--------
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\x
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(1 row)
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-- test updating of unrelated column
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UPDATE image SET title = 'beautiful picture' WHERE title = 'beautiful image';
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SELECT lo_get(43214);
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lo_get
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--------
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\x
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(1 row)
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DELETE FROM image;
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SELECT lo_get(43214);
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ERROR: large object 43214 does not exist
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DROP TABLE image;
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