將多個資料庫中的某列資料同步時需要用到mysql觸發器，以下可做參考，已簡單測試ok.
//修改紅棗的積分時觸發
drop trigger if exists u_hongzaocount;
delimiter $$
create trigger u_hongzaocount after update on
hongzao.pre_common_member_count
for each row
begin
declare v int(10);
declare vj int(10);
set v =(select extcredits2 from
qifangjie.pre_common_member_count where uid=new.uid);
set vj =(select extcredits2 from
jifenshop.pre_common_member_count where uid=new.uid);
if (new.extcredits2>old.extcredits2 and new.extcredits2>v) or
(new.extcredits2old.extcredits2 and new.extcredits2>vj)
or (new.extcredits20 then
set new.extcredits2=v;
end if;
end$$
//修改七紡街的積分時觸發
drop trigger if exists u_qifangjiecount;
delimiter $$
create trigger u_qifangjiecount after update on
qifangjie.pre_common_member_count
for each row
begin
declare v int(10);
declare vj int(10);
set v =(select extcredits2 from
hongzao.pre_common_member_count where uid=new.uid);
set vj =(select extcredits2 from
jifenshop.pre_common_member_count where uid=new.uid);
if (new.extcredits2>old.extcredits2 and new.extcredits2>v) or
(new.extcredits2old.extcredits2 and new.extcredits2>vj)
or (new.extcredits20 then
set new.extcredits2=v;
end if;
end$$
//修改積分**的積分時觸發
drop trigger if exists u_jifenshopcount;
delimiter $$
create trigger u_jifenshopcount after update on
jifenshop.pre_common_member_count
for each row
begin
declare v int(10);
declare vj int(10);
set v =(select extcredits2 from
hongzao.pre_common_member_count where uid=new.uid);
set vj =(select extcredits2 from
qifangjie.pre_common_member_count where uid=new.uid);
if (new.extcredits2>old.extcredits2 and new.extcredits2>v) or
(new.extcredits2old.extcredits2 and new.extcredits2>vj)
or (new.extcredits2=vj then
set new.extcredits2=v;
elseif vset new.extcredits2=vj;
end if;
end$$
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