mysql - 将 PostgreSQL 存储过程迁移到 MYSQL

Question

我有以下 PostgreSQL，我想重写它以使其与 MySQL 存储函数兼容。

CREATE OR REPLACE FUNCTION test.yearly_demand_function(IN paramstartdate date, 
                                                       OUT network character varying, 
                                                       OUT season_number integer,
                                                       OUT week_trans numeric,
                                                       OUT month_trans numeric, 
                                                       OUT year_trans numeric )
  RETURNS SETOF record AS
$BODY$

 BEGIN
    RETURN QUERY
        (select qq.network::varchar,
        qq.season_number,
        qq.week_trans::numeric,
        qq.month_trans::numeric,
        qq.year_trans::numeric
        from 
            ( 
            SELECT coalesce(nullif(mpf.studio,''),fi.name) AS network,
            coalesce(mpf.season_number, mpf.reported_season_number) AS season_number ,
            sum(case when activity_date >= date_trunc('week', paramStartDate::timestamp) - interval '7 day' and activity_date <= paramStartDate then mpf.units_sold else 0 END) as week_trans, 
            sum(case when activity_date >= date_trunc('month', paramStartDate::timestamp) and activity_date <= paramStartDate then mpf.units_sold else 0 END) as month_trans,
            sum(case when activity_date >= date_trunc('year', paramStartDate::timestamp) and activity_date <= paramStartDate then mpf.units_sold else 0 END) as year_trans
            FROM customer.dim_product_view mpf 
            left join customer.feed_indicator fi on mpf.series_name = fi.indicator_value
            and mpf.series_name = fi.indicator_value
            left join 
            (
            select p.series_name,p.season_number,count(*) as episode_count
            from product p
            where source in ('Amway','FifthThird')
            and p.episode_number is not null
            group by 1,2) as pec on mpf.series_name = pec.series_name
            and mpf.season_number = pec.season_number
            WHERE mpf.activity_date BETWEEN date_trunc('year', paramStartDate::timestamp) AND paramStartDate
            AND 1=1 
            AND ( mpf.demographic is null or '' not in ( '' ) or ('' in ( '' ) and mpf.demographic = 'Persons') ) 
            AND mpf.customer_product_id not ilike '%unallocated%'
            GROUP BY 1,2,3,7,34,35,36
            )qq
        );

end;
$BODY$
  LANGUAGE plpgsql VOLATILE
  COST 100
  ROWS 1000;
ALTER FUNCTION yearly_demand_function(date);

现在我不知道如何从上面的 PostgreSQL(RETURN QUERY 部分)为 MYSQL 编写 RETURNS SETOF 记录 AS

虽然我已经开始为 MY SQL 编写存储过程，如下

-- DROP FUNCTION IF EXISTS looptest;
DELIMITER $$

CREATE FUNCTION test.yearly_demand_function(    IN paramstartdate date,
                                                OUT network varchar(256), 
                                                OUT season_number integer,
                                                OUT week_value numeric,
                                                OUT month_value numeric, 
                                                OUT year_value numeric
        ) RETURNS <What to Write >
          LANGUAGE SQL  
BEGIN

  RETURN QUERY
        (select qq.network::varchar,
        qq.season_number,
        qq.week_value::numeric,
        qq.month_value::numeric,
        qq.year_value::numeric
        from 
            ( 
            SELECT coalesce(nullif(mm.studio,''),fi.name) AS network,
            coalesce(mm.season_number, mm.reported_season_number) AS season_number ,
            sum(case when final_date >= date_trunc('week', paramStartDate::timestamp) - interval '7 day' and final_date <= paramStartDate then mm.units_sold else 0 END) as week_value, 
            sum(case when final_date >= date_trunc('month', paramStartDate::timestamp) and final_date <= paramStartDate then mm.units_sold else 0 END) as month_value,
            sum(case when final_date >= date_trunc('year', paramStartDate::timestamp) and final_date <= paramStartDate then mm.units_sold else 0 END) as year_value
            FROM customer.product_view mm 
            left join customer.f_indicator fi on mm.series_name = fi.indicator_value
            and mm.series_name = fi.indicator_value
            left join 
            (
            select p.name,p.s_number,count(*) as episode_count
            from product p
            where source in ('Amway','FifthThird')
            and p.e_number is not null
            group by 1,2) as tt on mm.series_name = tt.series_name
            and mm.season_number = tt.season_number
            WHERE mm.final_date BETWEEN date_trunc('year', paramStartDate::timestamp) AND paramStartDate
            AND 1=1 
            AND ( mm.demographic is null or '' not in ( '' ) or ('' in ( '' ) and mm.demographic = 'Persons') ) 
            AND mm.customer_product_id not ilike '%unallocated%'
            GROUP BY 1,2,3,7,34,35,36
            )qq
        );


END;
$$
DELIMITER 

如何从上面的 PostgreSQL(RETURN QUERY 部分)为 MYSQL 编写 RETURNS SETOF 记录 AS

Answer 1

使用CREATE PROCEDURE语法代替CREATE FUNCTION。然后，您可以在该 block 内编写普通的 SELECT 语句。要执行您创建的存储过程，请使用 CALL 语法(即 CALL test.yearly_demand_function('2013-01-01'))。您也不需要指定 5 个OUT 参数。 5 个 OUT 参数的值将仅对应于您将在 SELECT 语句中指定的 5 列。