postgresql和mysql语句区别_postgresql和mysql语句区别

下面是MySQL和postgresql的语句区别，有需要的可以借鉴学习

1 UPDATE

1.1更新并返回

MySQL：

SELECT temp_lo,temp_hi,prcp FROM UPDATE wheather SET temp_lo =

temp_lo+1,temp_hi = temp_lo+15 WHERE city = ‘San Francisco’;

PostgreSQL：

UPDATE wheather SET temp_lo = temp_lo+1,temp_hi = temp_lo+15 WHERE city =

‘San Francisco’ RETURNING temp_lo,temp_hi;

1.2 表关联多字段更新

MySQL：无

PostgreSQL：

UPDATE accounts SET (Contact_last_name,cONtact_first_name) = (SELECT

Last_name,first_name FROM salesmen WHERE salesmen.id = accounts.sales_id);

2 INSERT

2.1 插入并返回

MySQL：无

PostgreSQL：

INSERT INTO distributors (did,dname) VALUES (DEFAULT,’XYZ’) RETURNING did;

2.2 插入冲突则更新

MySQL：INSERT INTO distributors (did,dname) VALUES (5,’Gizmo’),(6,’INc’) ON

DUPLICATE KEY UPDATE dname = EXCLUDED.dname;

PostgreSQL：INSERT INTO distributors (did,dname) VALUES (5,’Gizmo’),(6,’INc’) ON

CONFLICT (did) DO UPDATE SET dname = EXCLUDED.dname;

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2.3 插入冲突则什么都不做

MySQL：INSERT IGNORE INTO distributors (did,dname) VALUES (9,’Design’);

PostgreSQL：INSERT INTO distributors (did,dname) VALUES (9,’Design’) ON CONFLICT ON

CONSTRAINT distributors_pkey DO NOTHING;

3 SELECT

无

4 DELETE

4.1 删除并返回删除的内容

MySQL：无

PostgreSQL：DELETE FROM tasks WHERE status = ‘DONE’ RETURNING *;