Question

我正在尝试使用以下函数编写mysql存储过程：

输入是报告参数，包括报告类型，要运行的数据库反对和一些日期和过滤器参数
该过程在表（报告）中查找报告并读取报告参数。
某些报告是简单查询，而其他报告是2个报告（isunion=1）
从报告表中读取报告参数后，该过程将这些参数传递给build_report函数，该函数将它放在一起返回sql查询。
在单个查询的情况下，程序完美地工作（即只有1个报告部分），但是有2个部分，程序失败。似乎无法从中获得价值 build_report函数，即使是多部分查询的part1 与具有单个查询的报告的情况几乎相同（is_union = 0），但从报告表中获取部件的report_id除外。

我错过了什么？任何见解都会非常感激。

以下程序在isunion=0时完美无效，但在isunion=1时失败（即使我完全退出第2部分）

    CREATE PROCEDURE `runreport_u`(
    in all_active INT(1),
    in reportid INT(10), 
    in db_id INT(10), 
    in start_date date, 
    in end_date date, 
    in inc_grpby INT(1), 
    OUT qry_part varchar(20000), #only outputing these to help debug
    OUT qry_part1 varchar(20000),
    OUT qry_part2 varchar(50000),
    OUT qry varchar(40000),
    OUT union_rep_id1 int(10),
    OUT union_rep_id2 int(10),
    OUT isunion int(10))
    BEGIN
    # purpose - this procedures looks up the specifications of a report query in table report. If the report is a single query the procedure works perfectly (case isunion=0) . When the qry is made up of 2 queries to be unionized, the build_report function which builds the parts seems to return nothing. 

    DECLARE part int DEFAULT NULL;

    # is this report a union
    SELECT is_union INTO isunion FROM report WHERE report_id=@reportid;

    IF isunion=0 THEN
    #report is not a union
            SET part=1;
            SET union_rep_id1=reportid;
          SET qry_part = build_report(all_active,union_rep_id1,db_id,start_date,end_date,inc_grpby); 
    #log the components into gen table (more for debugging than anything else)
            INSERT INTO gen (report_number,run_date,part_number,part_report_number,qry_part,part_order,param_all_active,param_report_id,param_db_id,param_start_date,param_end_date,param_incgrp)   VALUES (reportid, now(),part,COALESCE(union_rep_id1,999),qry_part,part,all_active,reportid,db_id,start_date,end_date,inc_grpby);        

    SET qry=qry_part;

    ELSE 
    #report has 2 or more parts
    #*** first part
        SET part=1;
    #set the first report part - works (returns same union_rep_id as above)     
        SELECT union_report_id1 INTO union_rep_id1 FROM report WHERE report_id=reportid;
    #get the query - in principle identical to the above but works above and returns nothing here 
            SET qry_part1 = build_report(all_active,union_rep_id1,db_id,start_date,end_date,inc_grpby); 

            INSERT INTO gen (report_number,run_date,part_number,part_report_number,qry_part,part_order,param_all_active,param_report_id,param_db_id,param_start_date,param_end_date,param_incgrp)   VALUES (reportid, now(),part,COALESCE(union_rep_id1,999),qry_part1,part,all_active,reportid,db_id,start_date,end_date,inc_grpby);       

    #*** second part
        SET part=2;
        SELECT union_report_id2 INTO union_rep_id2 FROM report WHERE report_id=reportid;
          SET qry_part2 = build_report(all_active,union_rep_id2,db_id,start_date,end_date,inc_grpby); 
            INSERT INTO gen (report_number,run_date,part_number,part_report_number,qry_part,part_order,param_all_active,param_report_id,param_db_id,param_start_date,param_end_date,param_incgrp)   VALUES (reportid, now(),part,COALESCE(union_rep_id2,999),qry_part,part,all_active,reportid,db_id,start_date,end_date,inc_grpby);        

    #*******
    #join the parts together in UNION
    SET qry=CONCAT(qry_part,' UNION ',qry_part2);

    END IF;

#had to add the line below otherwise Prepare stmt failed to recognize qry as variable

    SET @final_qry=qry;

    PREPARE stmt FROM @final_qry;
    EXECUTE stmt;
    DEALLOCATE PREPARE stmt;

    #fails if isunion=1

    END

MySQL存储过程的行为不一致

0 个答案: