postgresql - 尝试使用 plpgsql 将数据插入时间戳字段时出错

Question

我有以下 plpgsql 函数:

CREATE OR REPLACE FUNCTION test_func(OUT pid bigint)
    RETURNS bigint AS
  $BODY$
    DECLARE
      current_time timestamp with time zone = now();
    BEGIN
      INSERT INTO "TEST"(
        created)
        VALUES (current_time) RETURNING id INTO pid;
    END
  $BODY$
  LANGUAGE plpgsql;

select * from test_func();

上面给出了一个错误:

column "created" is of type timestamp with time zone but expression is of type time with time zone

没有函数的插入查询:

INSERT INTO "TEST"(
        created)
        VALUES (now()) RETURNING id INTO pid;

或者如果 now() 直接使用而不定义变量，它就可以工作。

Answer 1

CURRENT_TIME是 reserved word (和一个特殊的功能)，你不能用它作为变量名。此处不需要变量:

CREATE OR REPLACE FUNCTION test_func(OUT pid bigint) AS
$func$
BEGIN
   INSERT INTO "TEST"(created)
   VALUES (now())
   RETURNING id
   INTO   pid;
END
$func$
LANGUAGE plpgsql;

now() 是一个 STABLE 函数。它不会在同一笔交易中发生变化。无需将结果捕获到变量中。

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