postgresql - WITH 语句中的查询是否在 PostgreSQL 的单个事务中执行？

Question

我在 WITH 语句中做了很多查询。他们应该在一个事务中。我应该在事务中显式地覆盖我的大查询还是没有必要？

这是我的查询的粗略示例:

WITH
    remains_actual AS (
        SELECT
            ...
    )
    affected_remains AS (
        INSERT INTO
            ...
        ON CONFLICT (...) DO UPDATE SET
            ...
        RETURNING
            ...
    )
    affected_products AS (
        SELECT DISTINCT
            ...
    )
INSERT INTO
    ....

Answer 1

来自docs :

PostgreSQL actually treats every SQL statement as being executed within a transaction. If you do not issue a BEGIN command, then each individual statement has an implicit BEGIN and (if successful) COMMIT wrapped around it.

WITH 语句仍算作单个语句，因此它将在隐式事务 block 中运行。

您可以使用一些返回当前事务 ID 的 CTE 自行测试:

with
  tx1 as (select txid_current()),
  tx2 as (select txid_current())
select * from tx1, tx2;

 txid_current | txid_current
--------------+--------------
        12814 |        12814
(1 row)