使用“ ON CONFLICT”子句语义插入行的postgresql方式

INSERT INTO foo (x, y, z) VALUES (1, 2, 3) ON CONFLICT replace;

delete from foo where x=1; INSERT INTO foo (x, y, z) VALUES (1, 2, 3) ON CONFLICT replace;

ON CONFLICT

/**
CREATE TABLE foo(id serial primary key, content text unique);
**/

WITH replace AS (
    DELETE FROM foo
    WHERE
        content = \'bar\'
    RETURNING content
)
INSERT INTO 
    foo(content) -- values:
SELECT
    *
FROM replace RIGHT JOIN (SELECT CAST(\'bar\' AS text) as content) sub USING(content);