mysql存储过程嵌套循环并分页处理数据

Posted 2020-10-07 HEWU

业务背景：公司存证产品升级，随着数据量的增加，存证产品线按业务分表，导致以往的存证关联数据需要做数据同步更新。版本发布前，通过当前存储过程解决数据升级问题。

##创建存证文档关联情况下更新所用存储过程

CREATE PROCEDURE evi_doc_refs_eid_deal()
begin
    declare pageNum int default 0;
    declare totalSize int default 0;
    declare pageSize int default 5;
    declare totalPage int DEFAULT 0;
    declare startIndex int default 0;
    select count(*) into totalSize from osv_service_evidence where type != 11 and type !=12 and type !=50  ;
    set totalPage = totalSize/pageSize;        
        while ( pageNum<totalPage-1) do 
                #对分页的起始下标计算，以便分页查询时使用
                set startIndex = pageNum *pageSize;
                #开启事务
              　START TRANSACTION;
                #嵌套内部分页查询，通过游标处理分页查询结果记录
                begin 
               #声明变量
                   declare eviId varchar(50);
                   declare evidenceEid varchar(50);
                   declare done int default 0;
                   declare mark varchar(2);
                   declare eid_value varchar(50);
                   declare type_value int default 0;
                   declare eid_mark varchar(50);
　　　　            declare num int DEFAULT 0;
            　　　　#定义分页查询结果的游标
                   declare i_cur cursor for select id from osv_service_evidence where type !=11 and type !=12 and type !=50 limit startIndex,pageSize;
                   declare continue handler for sqlstate ‘09000‘ set done = 1;
            
                   open i_cur; 
                       fetch next from i_cur into eviId;
            
                       WHILE (done = 0 ) do
                          #判断每页中处理数据的下标index
                          set num = num+1;
                          select type into type_value  from osv_service_evidence where id = eviId;      
                          select e.eid into eid_value from osv_service_evidence e where id = eviId;
                                
                          if(0 =type_value|null = eid_value) then fetch next from i_cur into eviId;
                          end if;
                  
                  　　　　　　#数据处理
                            if     type_value =40 then set mark = ‘O‘; set eid_mark=concat(mark,eid_value);update evi_doc_refs set docEid = eid_mark where docEviId = eviId;
                            elseif type_value =11 then set mark = ‘S‘; set eid_mark=concat(mark,eid_value);update evi_doc_refs set docEid = eid_mark where docEviId = eviId;set done = 0;
                            end if;
                                        
                  　　　　　#如果当前页处理的数据已达页记录数值，通过done退出内部循环，进入外部循环
                  　　　　  IF num = pageSize THEN set done = 1;
                  　　　　  #否则继续当前循环
                 　　　　　　ELSEIF num !=pageSize THEN set done =0;
                      　　　　　　fetch next from i_cur into eviId;
                  　　　　　 END IF;
                       END WHILE;
            　　　　#关闭游标
                   close i_cur;
                end ;
        COMMIT;
    　　#更新下一次处理的页码，+1
        set pageNum = pageNum+1;
    end while;
END;

call evi_doc_refs_eid_deal();

 

##创建出证订单表中存证编号为null的情况下更新所用存储过程
create procedure evi_order_refs_eid_deal()
begin
declare original_eviId varchar(50);
declare evidenceEid varchar(50);
declare done int default 0;
declare mark varchar(2);
declare eid_value varchar(50);
declare type_value int default 0;
declare eid_mark varchar(50);
# declare existence boolean ;
##
declare cur cursor for select eviId  from evi_order_refs where evidenceEid is null order by createTime desc;
##异常处理(触发sql语句失败，执行结束)
declare continue handler for sqlstate ‘09000‘ set done = 1;
open cur;
    ##取出游标值至变量中
    fetch next from cur into original_eviId;
　　repeat
    if not done then 
       
                    select type into type_value  from osv_service_evidence where id = original_eviId;
                    #逻辑判断，如果eviId确实在存证表中无记录，直接忽略该条出证记录
                    
                    select e.eid into eid_value from osv_service_evidence e where id = original_eviId;
                    #逻辑判断，如果eviId确实在存证表中无记录，直接忽略该条出证记录
                    if(0 =type_value|null = eid_value) then fetch next from cur into original_eviId;
                    end if;
                        
                    if     type_value =40 then set mark = ‘O‘;set eid_mark=concat(mark,eid_value);update evi_order_refs set evidenceEid = eid_mark where eviId = original_eviId;
                    elseif type_value =11 then set mark = ‘S‘;set eid_mark=concat(mark,eid_value);update evi_order_refs set evidenceEid = eid_mark where eviId = original_eviId;else  set done = 0;
　　　　　　　　　　　　end if;
    　　　　　　end if;
        #if(done = 1) then leave cur;
        
        ##重新抓取数据进入循环
    fetch next from cur into original_eviId;
##结束循环
until done end repeat;
##关闭游标
close cur;
end ;