尝试使用plpgsql将数据插入时间戳字段时出错

Question

我有以下plpgsql功能：

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

无功能的插入查询：

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

或如果直接使用now()而没有定义变量则可以使用。

Answer 1

CURRENT_TIME是reserved word（和一个特殊函数），您不能将其用作变量名。你不需要在这里开始使用变量：

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STABLE函数。它不会在同一个事务中发生变化。无需将结果捕获到变量中。

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