SQL 在 Postgres 中将 Const Integer 转换为 Bigint
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原文地址: http://stackoverflow.com/questions/9793422/
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Cast Const Integer to Bigint in Postgres
提问by Nick Vaccaro
I'm getting the below error while running the below script. My goal is to create a function in Postgres to return 1 as a bigint. Help please!
运行以下脚本时出现以下错误。我的目标是在 Postgres 中创建一个函数以将 1 作为 bigint 返回。请帮忙！
hashtagpostgresnoobie
标签postgresnoobie
ERROR: function result type must be bigint because of OUT parameters
错误：由于 OUT 参数，函数结果类型必须是 bigint
CREATE OR REPLACE FUNCTION GetNumberOne(
OUT numberone bigint)
RETURNS SETOF record AS
$BODY$
SELECT CAST(1 AS BIGINT) AS "NUMBERONE";
$BODY$
LANGUAGE sql VOLATILE;
回答by Timur Sadykov
You've suddenly encountered the feature ) Record needs two and more fields. So when you have only one out variable, then result must be scalar.
您突然遇到了功能 ) 记录需要两个或更多字段。因此，当您只有一个输出变量时，结果必须是标量。
So, you can simply do what compilers ask )
因此，您可以简单地执行编译器要求的操作）
CREATE OR REPLACE FUNCTION GetNumberOne(
OUT numberone bigint)
RETURNS bigint AS
$BODY$
SELECT CAST(1 AS BIGINT) AS "NUMBERONE";
$BODY$
LANGUAGE sql VOLATILE;
plpgsql example:
plpgsql 示例：
CREATE OR REPLACE FUNCTION NumberOne()
RETURNS bigint AS
$BODY$
DECLARE num bigint;
BEGIN
num := 1;
RETURN num;
END
$BODY$
LANGUAGE plpgsql VOLATILE;
select * from NumberOne()
