Om du lägger till en boolesk uppdaterad kolumn till people
tabell:
ALTER TABLE people ADD COLUMN updated bool DEFAULT FALSE;
sedan kan du identifiera uppdaterade rader genom att ställa in updated = TRUE
i DO UPDATE SET
klausul:
INSERT INTO people (SELECT * FROM people_update)
ON CONFLICT (name,surname)
DO UPDATE SET age = EXCLUDED.age , street = EXCLUDED.street , city = EXCLUDED.city
, postal = EXCLUDED.postal
, updated = TRUE
WHERE
(people.age,people.street,people.city,people.postal) IS DISTINCT FROM
(EXCLUDED.age,EXCLUDED.street,EXCLUDED.city,EXCLUDED.postal)
RETURNING *;
Till exempel,
CREATE TABLE test.people (
name text
, surname text
, age float
, street text
, city text
, postal int
);
CREATE UNIQUE INDEX people_idx on people (name, surname);
ALTER TABLE people ADD COLUMN updated bool;
ALTER TABLE people ADD COLUMN prior_age float;
ALTER TABLE people ADD COLUMN prior_street text;
ALTER TABLE people ADD COLUMN prior_city text;
ALTER TABLE people ADD COLUMN prior_postal int;
INSERT INTO people (name, surname, age, street, city, postal) VALUES
('Sancho', 'Panza', 414, '1 Manchego', 'Barcelona', 01605)
, ('Oliver', 'Twist', 182, '2 Stilton', 'London', 01837)
, ('Quasi', 'Modo', 188, $$3 Rue d'Arcole$$, 'Paris' , 01831 )
;
CREATE TABLE test.people_update (
name text
, surname text
, age float
, street text
, city text
, postal int
);
INSERT INTO people_update (name, surname, age, street, city, postal) VALUES
('Sancho', 'Panza', 4140, '10 Idiazabal', 'Montserrat', 16050)
, ('Quasi', 'Modo', 1880, $$30 Champs Elysée$$ , 'Paris', 18310 )
, ('Pinocchio', 'Geppetto', 1380, '40 Nerbone', 'Florence', 18810)
;
INSERT INTO people (SELECT * FROM people_update)
ON CONFLICT (name,surname)
DO UPDATE SET
updated = TRUE
, prior_age = (CASE WHEN people.age = EXCLUDED.age THEN NULL ELSE people.age END)
, prior_street = (CASE WHEN people.street = EXCLUDED.street THEN NULL ELSE people.street END)
, prior_city = (CASE WHEN people.city = EXCLUDED.city THEN NULL ELSE people.city END)
, prior_postal = (CASE WHEN people.postal = EXCLUDED.postal THEN NULL ELSE people.postal END)
, age = EXCLUDED.age
, street = EXCLUDED.street
, city = EXCLUDED.city
, postal = EXCLUDED.postal
WHERE
(people.age,people.street,people.city,people.postal) IS DISTINCT FROM
(EXCLUDED.age,EXCLUDED.street,EXCLUDED.city,EXCLUDED.postal)
RETURNING *;
ger
| name | surname | age | street | city | postal | updated | prior_age | prior_street | prior_city | prior_postal |
|------------+----------+------+------------------+------------+--------+---------+-----------+----------------+------------+--------------|
| Sancho | Panza | 4140 | 10 Idiazabal | Montserrat | 16050 | t | 414 | 1 Manchego | Barcelona | 1605 |
| Quasi | Modo | 1880 | 30 Champs Elysée | Paris | 18310 | t | 188 | 3 Rue d'Arcole | | 1831 |
| Pinocchio | Geppetto | 1380 | 40 Nerbone | Florence | 18810 | f | | | | |
Den updated
kolumnen visar ('Sancho', 'Panza')
och ('Quasi', 'Modo')
rader har uppdaterats, och('Pinocchio', 'Geppetto')
är en ny inlaga.