如何在 postgres 函数中返回表及其总数

Question

我是 postgresql 的新手，并创建如下函数

CREATE OR REPLACE FUNCTION GetLogs(
    _from Date, 
    _to Date,  
    _sortBy TEXT, 
    _orderby INT, 
    _page INT, 
    _row INT)
 RETURNS TABLE (
     "Id" UUID, 
     "RequestHeaders" text, 
     "RequestContent" text, 
     "ResponseHeaders" text, 
     "ResponseContent" text, 
     "ResponseCode" integer, 
     "ExecutionTimeMs" integer, 
     "Description" text,
     "RecordedOn" timestamp with time zone, 
     "Username" character varying, 
     "Exception" text) 
AS $$
BEGIN
    RETURN QUERY 
        SELECT COUNT(1)
        FROM dbo."Logs" log
        where log."RecordedOn" >= $1 and log."RecordedOn" <= $2;

    RETURN QUERY 
        SELECT log.*
        FROM dbo."Logs" log
        where log."RecordedOn" >= $1 and log."RecordedOn" <= $2
        Offset ($5-1) * $6
        Limit $6;
END;
$$ LANGUAGE plpgsql;

，并使用

调用它

select * from GetLogs('2020-02-11','2020-02-12','Date',0,1,10)

我希望这将是一个计数和表格数据，但错误是

ERROR:  structure of query does not match function result type
DETAIL:  Returned type bigint does not match expected type uuid in column 1.

有人能解决吗？

Answer 1

您不能返回结构与 RETURNS TYPE 不匹配的结果（在您的情况下 - 桌子）。 相反，您可以使用窗口函数将RowsCount 添加到每个返回的行。

CREATE OR REPLACE FUNCTION GetLogs(
    _from Date, 
    _to Date,  
    _sortBy TEXT, 
    _orderby INT, 
    _page INT, 
    _row INT)
 RETURNS TABLE (
     "Id" UUID, 
     "RequestHeaders" text, 
     "RequestContent" text, 
     "ResponseHeaders" text, 
     "ResponseContent" text, 
     "ResponseCode" integer, 
     "ExecutionTimeMs" integer, 
     "Description" text,
     "RecordedOn" timestamp with time zone, 
     "Username" character varying, 
     "Exception" text,
     "RowsCount" integer
)
AS $$
DECALARE
    RowsCount integer;
BEGIN

    RETURN QUERY 
        SELECT log.*, COUNT(*) OVER() AS RowsCount
        FROM dbo."Logs" log
        WHERE log."RecordedOn" >= $1 AND log."RecordedOn" <= $2
        OFFSET ($5-1) * $6
        LIMIT $6;
END;
$$ LANGUAGE plpgsql;