postgreSQL存储过程函数的使用方法与常见问题解决

postgre存储过程使用PL/pgSQL语言,


PL/pgSQL是一种块结构的语言,基本方式如下:
CREATE OR REPLACE FUNCTION 函数名(参数1,[整型 int4, 整型数组 _int4, …])
RETURNS 返回值类型 AS
$BODY$
DECLARE
变量声明
BEGIN
函数体
END;
$BODY$
LANGUAGE ‘plpgsql’ VOLATILE;

 功能描述:从查询的结果中利用表名查询所需内容。

create or replace function fff(userid int) 
returns setof record as   --返回类型,结果集
    $$
    declare
        sql varchar; --定义变量
	   asql varchar;
        re record;
	fav record;
    begin
        sql = 'select DISTINCT type as tablename from bmap_favorite where type<>'''||'0'|| '''and userid='''|| userid ||'''';
	-----sql
        for re in execute sql loop     --循环执行后的结果集
           
		asql = 'select f.gid,f.favtime,a.name,a.city,a.district,a.province,a.address,st_x(a.geom) as x,st_y(a.geom) as y
 from '|| re.tablename ||' a, bmap_favorite f where a.gid = cast(f.gid as INTEGER) and f.userid=2 and f.type='''|| re.tablename ||'''';
		for fav in execute asql loop
			return next fav;
		end loop;
        end loop;
        
        return;
    end
    $$
language plpgsql;
 

1.执行存储过程中,出现“set-valued function called in context that cannot accept a set”的错误

在数据库里执行函数,可以写“select funciton();”也可以写“select * from function()”

2.出现PostgreSQL: ERROR: 42601: a column definition list is required for functions returning “record”的错误
select * from fff(2) as f(gid varchar,favtime varchar,name VARCHAR,city varchar, 
district varchar,provice varchar, address varchar, x float,y float) --执行存储过程
需要在添加查询内容对应的类型。


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