我对在PostgreSQL中编写存储函数以及一般编程都很陌生。我试图编写一个带有输入参数并返回存储在临时表中的结果集的函数。
我在函数中执行以下步骤:
- 获取所有消费者的列表,并将其ID存储在临时表中。
- 迭代遍历特定表格,并检索与上述列表中每个值对应的值,并将其存储在临时表中。
- 返回临时表。
下面是我自己尝试编写的函数:
create or replace function getPumps(status varchar) returns setof record as $$ (setof record?)
DECLARE
cons_id integer[];
i integer;
temp table tmp_table;--Point B
BEGIN
select consumer_id into cons_id from db_consumer_pump_details;
FOR i in select * from cons_id LOOP
select objectid,pump_id,pump_serial_id,repdate,pumpmake,db_consumer_pump_details.status,db_consumer.consumer_name,db_consumer.wenexa_id,db_consumer.rr_no into tmp_table from db_consumer_pump_details inner join db_consumer on db_consumer.consumer_id=db_consumer_pump_details.consumer_id
where db_consumer_pump_details.consumer_id=i and db_consumer_pump_details.status=$1--Point A
order by db_consumer_pump_details.consumer_id,pump_id,createddate desc limit 2
END LOOP;
return tmp_table
END;
$$
LANGUAGE plpgsql;
然而,我不确定我的方法是否正确,并且是否在上面标记为A和B的点。同时,在尝试创建临时表时出现了大量错误。
编辑:已使该函数可用,但当我尝试运行该函数时会出现以下错误。
ERROR: array value must start with "{" or dimension information
这是我修改后的函数。
create temp table tmp_table(objectid integer,pump_id integer,pump_serial_id varchar(50),repdate timestamp with time zone,pumpmake varchar(50),status varchar(2),consumer_name varchar(50),wenexa_id varchar(50),rr_no varchar(25));
select consumer_id into cons_id from db_consumer_pump_details;
FOR i in select * from cons_id LOOP
insert into tmp_table
select objectid,pump_id,pump_serial_id,repdate,pumpmake,db_consumer_pump_details.status,db_consumer.consumer_name,db_consumer.wenexa_id,db_consumer.rr_no from db_consumer_pump_details inner join db_consumer on db_consumer.consumer_id=db_consumer_pump_details.consumer_id where db_consumer_pump_details.consumer_id=i and db_consumer_pump_details.status=$1
order by db_consumer_pump_details.consumer_id,pump_id,createddate desc limit 2;
END LOOP;
return query (select * from tmp_table);
drop table tmp_table;
END;
$$
LANGUAGE plpgsql;