Oracle基礎:4: sql執行錯誤時的控制方式
多條sql執行時如果在中間的語句出現錯誤,後續會不會直接執行,如何進行設定,以及其他資料庫諸如Mysql是如何對應的,這篇文章將會進行簡單的整理和說明。
環境準備
使用Oracle的精簡版建立docker方式的demo環境,詳細可參看:
多行語句的正常執行
對上篇文章建立的兩個欄位的學生資訊表,正常新增三條資料,詳細如下:
# sqlplus system/[email protected] <<EOF > desc student > select * from student; > insert into student values (1001, 'liumiaocn'); > insert into student values (1002, 'liumiao'); > insert into student values (1003, 'michael'); > commit; > select * from student; > EOF SQL*Plus: Release 11.2.0.2.0 Production on Sun Oct 21 12:08:35 2018 Copyright (c) 1982, 2011, Oracle. All rights reserved. Connected to: Oracle Database 11g Express Edition Release 11.2.0.2.0 - 64bit Production SQL> Name Null? Type ----------------------------------------- -------- ---------------------------- STUID NOT NULL NUMBER(4) STUNAME VARCHAR2(50) SQL> no rows selected SQL> 1 row created. SQL> 1 row created. SQL> 1 row created. SQL> Commit complete. SQL> STUID STUNAME ---------- -------------------------------------------------- 1001 liumiaocn 1002 liumiao 1003 michael SQL> Disconnected from Oracle Database 11g Express Edition Release 11.2.0.2.0 - 64bit Production #
多行語句中間出錯時的預設動作
問題:
三行insert語句,如果中間的一行出錯,預設的狀況下第三行會不會被插入進去?
我們將第二條insert語句的主鍵故意設定重複,然後進行確認第三條資料是否會進行插入即可。
# sqlplus system/[email protected] <<EOF desc student delete from student; select * from student; insert into student values (1001, 'liumiaocn'); insert into student values (1001, 'liumiao'); insert into student values (1003, 'michael'); select * from student; commit;> > > > > > EOF SQL*Plus: Release 11.2.0.2.0 Production on Sun Oct 21 12:15:16 2018 Copyright (c) 1982, 2011, Oracle. All rights reserved. Connected to: Oracle Database 11g Express Edition Release 11.2.0.2.0 - 64bit Production SQL> Name Null? Type ----------------------------------------- -------- ---------------------------- STUID NOT NULL NUMBER(4) STUNAME VARCHAR2(50) SQL> 2 rows deleted. SQL> no rows selected SQL> 1 row created. SQL> insert into student values (1001, 'liumiao') * ERROR at line 1: ORA-00001: unique constraint (SYSTEM.SYS_C007024) violated SQL> 1 row created. SQL> STUID STUNAME ---------- -------------------------------------------------- 1001 liumiaocn 1003 michael SQL> SQL> Disconnected from Oracle Database 11g Express Edition Release 11.2.0.2.0 - 64bit Production #
結果非常清晰地表明是會繼續執行的,在oracle中通過什麼來對其進行控制呢?
WHENEVER SQLERROR
答案很簡單,在oracle中通過WHENEVER SQLERROR來進行控制。
WHENEVER SQLERROR {EXIT [SUCCESS | FAILURE | WARNING | n | variable | :BindVariable] [COMMIT | ROLLBACK] | CONTINUE [COMMIT | ROLLBACK | NONE]}
WHENEVER SQLERROR EXIT
新增此行設定,即會在失敗的時候立即推出,接下來我們進行確認:
# sqlplus system/[email protected] <<EOF
WHENEVER SQLERROR EXIT
desc student
delete from student;
select * from student;
insert into student values (1001, 'liumiaocn');
insert into student values (1001, 'liumiao');
insert into student values (1003, 'michael');
select * from student;
commit;> > > > > > > > >
> EOF
SQL*Plus: Release 11.2.0.2.0 Production on Sun Oct 21 12:27:15 2018
Copyright (c) 1982, 2011, Oracle. All rights reserved.
Connected to:
Oracle Database 11g Express Edition Release 11.2.0.2.0 - 64bit Production
SQL> SQL> Name Null? Type
----------------------------------------- -------- ----------------------------
STUID NOT NULL NUMBER(4)
STUNAME VARCHAR2(50)
SQL>
2 rows deleted.
SQL>
no rows selected
SQL>
1 row created.
SQL> insert into student values (1001, 'liumiao')
*
ERROR at line 1:
ORA-00001: unique constraint (SYSTEM.SYS_C007024) violated
Disconnected from Oracle Database 11g Express Edition Release 11.2.0.2.0 - 64bit Production
#
WHENEVER SQLERROR CONTINUE
使用CONTINUE則和預設方式下的行為一致,出錯仍然繼續執行
# sqlplus system/[email protected] <<EOF
WHENEVER SQLERROR CONTINUE
desc student
delete from student;
select * from student;
insert into student values (1001, 'liumiaocn');
insert into student values (1001, 'liumiao');
insert into student values (1003, 'michael');
select * from student;
commit;> > > > > > > > >
> EOF
SQL*Plus: Release 11.2.0.2.0 Production on Sun Oct 21 12:31:54 2018
Copyright (c) 1982, 2011, Oracle. All rights reserved.
Connected to:
Oracle Database 11g Express Edition Release 11.2.0.2.0 - 64bit Production
SQL> SQL> Name Null? Type
----------------------------------------- -------- ----------------------------
STUID NOT NULL NUMBER(4)
STUNAME VARCHAR2(50)
SQL>
1 row deleted.
SQL>
no rows selected
SQL>
1 row created.
SQL> insert into student values (1001, 'liumiao')
*
ERROR at line 1:
ORA-00001: unique constraint (SYSTEM.SYS_C007024) violated
SQL>
1 row created.
SQL>
STUID STUNAME
---------- --------------------------------------------------
1001 liumiaocn
1003 michael
SQL>
Commit complete.
SQL> Disconnected from Oracle Database 11g Express Edition Release 11.2.0.2.0 - 64bit Production
#
Mysql中類似的機制
在2014年7月,mysql中使用source是否提供相關的類似機制的問題中,最終引入了Oracle此項功能在mysql中引入的建議,詳細請參看:
所以目前這只是一個sqlplus端的強化功能,並非標準,不同資料庫需要確認相應的功能是否存在。
總結
Oracle中使用WHENEVER SQLERROR進行出錯控制是否繼續,本文給出的例子非常簡單,詳細功能的使用可根據文中列出的Usage進行自行驗證和探索。
參考內容
https://docs.oracle.com/cd/E25178_01/server.1111/e16638/advisor.htm
https://docs.oracle.com/cd/B19306_01/server.102/b14357/ch12052.htm