PostgreSQL functions (stored procedure) returns an implementation of a plurality of records

PostgreSQL functions (stored procedure) returns an implementation of a plurality of records

Background: The use of function pg offer returns multiple records form rendering

Way: by cyclic

CREATE 
OR REPLACE FUNCTION "public"."f_get_traindata" ( OUT "o_item" VARCHAR, OUT "o_periodsnum" VARCHAR, OUT "o_trainday" VARCHAR, OUT "o_attendpersonnum" VARCHAR ) RETURNS SETOF "pg_catalog"."record" AS $BODY$ DECLARE
 rec record; -- 定义返回记录行
 o_sql TEXT; -- 定义执行的sql片段
BEGIN
  o_sql := 'SELECT item,periodsnum,trainday,attendpersonnum FROM bi_fact_traindata;';
-- 输出字段
FOR rec IN EXECUTE o_sql
loop
-- 将每个字段一一赋值给变量
 o_item := rec.item;
 o_periodsnum := rec.periodsnum;
 o_trainday := rec.trainday;
 o_attendpersonnum := rec.attendpersonnum;
RETURN NEXT;

END loop;
RETURN;
END;
$BODY$ LANGUAGE plpgsql VOLATILE COST 100 ROWS 1000

In this way too much trouble, you need a custom field, more complicated.

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Second way: Using the table

Use table

CREATE OR REPLACE FUNCTION "public"."f_get_appraisalindex" ( "o_indexid" VARCHAR ) 
-- 定义table
RETURNS TABLE (
		"o_indexname" VARCHAR,
		"o_standardrule" VARCHAR,
		"o_standardscore" VARCHAR,
		"o_losescore" NUMERIC,
		"o_orgstructname" VARCHAR,
		"o_appraisaldate" VARCHAR,
		"o_periodictime" VARCHAR,
		"o_periodictimelosescore" NUMERIC,
		"o_evaluatereason" VARCHAR 
		) AS $BODY$ 
BEGIN
		RETURN query 
-- 字段一一映射
SELECT
		tn_indexname,
		tn_standardrule,
		tn_standardscore,
		tn_losescore,
		tn_orgstructname,
		tn_appraisaldate,
		tn_periodictime,
		tn_periodictimelosescore,
		tn_evaluatereason 
	FROM
		tn_appraisalindex 
	WHERE
		tn_periodictimelosescore > 0 
	ORDER BY
		tn_indexid;
	
END;

$BODY$ LANGUAGE plpgsql VOLATILE COST 100 ROWS 1000

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Spread

How to define the situation there to the Senate and the Senate: do not need to be clear that the return way

(Source: https: //blog.csdn.net/qq_42535651/article/details/92089510)