PostgreSQL 函数工作一次然后出错

如何解决PostgreSQL 函数工作一次然后出错

这个功能...

CREATE OR REPLACE FUNCTION public.find_locations(
    search_text character varying,record_offset integer DEFAULT 0,fetch_quantity integer DEFAULT 20,sort_by character varying DEFAULT 'name',direction character varying DEFAULT 'ASC')
    RETURNS json
    LANGUAGE 'plpgsql'
AS $BODY$
BEGIN
  CREATE TEMP TABLE locations_found AS
  SELECT
    locations._id AS id,locations.name,locations.address,locations.city,locations.state,locations."zipCode",locations.phone,locations.map,locations.directions,locations.review,locations.parking,locations.active
  FROM locations
  WHERE search_text IS NULL OR search_text = '' OR LOWER(locations.name) LIKE LOWER(search_text) || '%'
  ORDER BY
    CASE 
      WHEN direction = 'ASC' THEN
        CASE
          WHEN sort_by = 'name' THEN locations.name
          WHEN sort_by = 'address' THEN locations.address
          WHEN sort_by = 'active' THEN locations.active::varchar
        END
    END ASC,CASE
      WHEN direction = 'DESC' THEN
        CASE
          WHEN sort_by = 'name' THEN locations.name
          WHEN sort_by = 'address' THEN locations.address
          WHEN sort_by = 'active' THEN locations.active::varchar
        END
    END DESC;

  RETURN  
   json_build_object(
      'count',(SELECT COUNT(*) FROM locations_found),'offset',record_offset,'limit',fetch_quantity,'results',(SELECT json_agg(locations_found.*) FROM locations_found OFFSET record_offset LIMIT fetch_quantity)
    );
END;
$BODY$;

我第一次调用它时效果很好。例如：

SELECT * FROM find_locations('north',2,'name','ASC');

在那之后，我得到：

错误：关系“locations_found”已经存在

最初，我什至没有明确删除临时表，因为我认为它会在事务执行后消失。

为什么临时表存在于第二个事务上？

更新：根据 a_horse_with_no_name 的指导，我更新了函数以使用通用表表达式 (CTE)：

CREATE OR REPLACE FUNCTION public.find_locations(
    search_text character varying,sort_by character varying DEFAULT 'name'::character varying,direction character varying DEFAULT 'ASC'::character varying)
    RETURNS json
    LANGUAGE 'plpgsql'
    COST 100
    VOLATILE ParaLLEL UNSAFE
AS $BODY$
DECLARE
  response json;
BEGIN
  WITH locations_found AS (
    SELECT
      locations._id AS id,locations.active
    FROM locations
    WHERE search_text IS NULL OR search_text = '' OR LOWER(locations.name) LIKE LOWER(search_text) || '%'
    ORDER BY
      CASE 
        WHEN direction = 'ASC' THEN
          CASE
            WHEN sort_by = 'name' THEN locations.name
            WHEN sort_by = 'address' THEN locations.address
            WHEN sort_by = 'active' THEN locations.active::varchar
          END
      END ASC,CASE
        WHEN direction = 'DESC' THEN
          CASE
            WHEN sort_by = 'name' THEN locations.name
            WHEN sort_by = 'address' THEN locations.address
            WHEN sort_by = 'active' THEN locations.active::varchar
          END
      END DESC
  )
  SELECT json_build_object(
      'count',(SELECT json_agg(locations_found.*) FROM locations_found OFFSET record_offset LIMIT fetch_quantity)
    ) INTO response;
    RETURN response;
END;
$BODY$;

解决方法

默认情况下，它们留在会话中。在提交时保留行 - 默认情况下。如果你想在提交后删除表，你应该在提交删除时创建它。