Oracle触发器表发生了变化触发器不能读它的解决方法(必看)_Oracle

Oracle触发器表发生了变化触发器不能读它的解决方法(必看)

2020-01-09 15:23jingxian Oracle

下面小编就为大家带来一篇Oracle触发器表发生了变化触发器不能读它的解决方法(必看)。小编觉得挺不错的，现在就分享给大家，也给大家做个参考。一起跟随小编过来看看吧

出现原因，是因为在更新的的表和读取的表是同一个表。

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									CREATE or replace TRIGGER T_userupdateT BEFORE update ON T_user REFERENCING OLD AS old NEW AS N_ROW  FOR EACH ROW 

									DECLARE U_xtfidemp1 varchar(36);

									 u_xtempcode1 varchar(20);

									 u_xtempcodeCount int:=0; 

									 U_xtfidempCount int:=0; 

									 u_id1 int:=0; 

									BEGIN

									 U_xtfidemp1:=:N_ROW.U_xtfidemp;

									 u_xtempcode1:=:N_ROW.u_xtempcode;

									 u_id1:=:N_ROW.u_id;

									 select count(u_xtempcode) into u_xtempcodeCount from eas.T_user where u_xtempcode is not null and u_xtempcode=u_xtempcode1 and u_id<>u_id1;

									 select count(U_xtfidemp) into U_xtfidempCount from eas.T_user where U_xtfidemp is not null and U_xtfidemp=U_xtfidemp1 and u_id<>u_id1; 

									 IF u_xtempcodeCount>0 or U_xtfidempCount>0 THEN

									     RAISE_APPLICATION_ERROR(-20001, 'eas.T_user u_xtempcode,U_xtfidemp,U_GZCode更新数据时有错误,有重复');

									 END IF;

									 end;

出现错误时，是因为触发器在T_userupdateT在T_user上，触发器内部有读取了T_user所以有错误。

修改如下

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									CREATE or replace TRIGGER T_userupdateT BEFORE update ON T_user REFERENCING OLD AS old NEW AS N_ROW  FOR EACH ROW 

									DECLARE U_xtfidemp1 varchar(36);

									 u_xtempcode1 varchar(20);

									 u_xtempcodeCount int:=0; 

									 U_xtfidempCount int:=0; 

									 u_id1 int:=0; 

									PRAGMA AUTONOMOUS_TRANSACTION;

									BEGIN

									 U_xtfidemp1:=:N_ROW.U_xtfidemp;

									 u_xtempcode1:=:N_ROW.u_xtempcode;

									 u_id1:=:N_ROW.u_id;

									 select count(u_xtempcode) into u_xtempcodeCount from eas.T_user where u_xtempcode is not null and u_xtempcode=u_xtempcode1 and u_id<>u_id1;

									 select count(U_xtfidemp) into U_xtfidempCount from eas.T_user where U_xtfidemp is not null and U_xtfidemp=U_xtfidemp1 and u_id<>u_id1; 

									 IF u_xtempcodeCount>0 or U_xtfidempCount>0 THEN

									     RAISE_APPLICATION_ERROR(-20001, 'eas.T_user u_xtempcode,U_xtfidemp,U_GZCode更新数据时有错误,有重复');

									 END IF;

									COMMIT;

									 end;