參數化選擇語句PSQL的輸出

Question

我使用的是基於8.3構建的postgresql版本。 我基於特定的IP地址運行大量查詢，並希望創建一個函數，該函數可以將IP地址作為類似於以下參數的參數傳遞：

CREATE OR REPLACE FUNCTION features.src_forensics(text)     
RETURNS SETOF rows as
$$

select src, action,
count(distinct date_trunc('day', receive_time) ) n_activeDay,
count(distinct source_IP) n_src,
count(distinct source_IP) / count(distinct date_trunc('day', receive_time)) n_src_per_day,
sum(bytes) as total_bytes,
min(receive_time) minTime,
max(receive_time) maxTime
from  table
where src = $1 
group by src, action ;

$$ LANGUAGE sql;

問題是上面的查詢沒有以我慣用的表格式返回select語句的輸出。 如果將10.10.0.1用作函數的IP地址輸入，如何獲得上面編寫的腳本，使其表現得像下面的select語句？

select src, action,
count(distinct date_trunc('day', receive_time) ) n_activeDay,
count(distinct source_IP) n_src,
count(distinct source_IP) / count(distinct date_trunc('day', receive_time)) n_src_per_day,
sum(bytes) as total_bytes,
min(receive_time) minTime,
max(receive_time) maxTime
from  table
where src = '10.10.0.1'
group by src, action;

Answer 1

我通常在返回任意列集時執行此操作：

RETURNS TABLE(
    src             text,
    action          text,
    n_activeDay     bigint,
    n_src           bigint,
    n_src_per_day   bigint,
    total_bytes     bigint,
    minTime         timestamptz,
    maxTime         timestamptz
) AS

如果您希望保留定義不變，則可以更改查詢函數的方式：

select * from features.src_forensics("a") AS f(
        src             text,
        action          text,
        n_activeDay     bigint,
        n_src           bigint,
        n_src_per_day   bigint,
        total_bytes     bigint,
        minTime         timestamptz,
        maxTime         timestamptz
    );