Oracle 2022-07-29

SQL开发知识：Oracle查询sql语句错误信息的控制和定位处理方式

在sqlplus中执行的sql出错之后应该如何处理和对应，多行sql语句或者存储过程的信息如何进行错误定位，这篇文章将结合实例进行简单地说明。

环境准备

使用Oracle的精简版创建docker方式的demo环境，详细可参看：

oracle@e871d42341c0:~$

因为dbms_utility.format_error_backtrace更多的场景是在于存储过程的错误定位，接下来我们使用一个简单的存储过程例子来进行确认错误行号定位, 先看一个正常的存储过程，把上面的内容稍微修改一下：

oracle@e871d42341c0:~$ cat /tmp/addstudent.sql
create or replace PROCEDURE addstudents
IS
student_count number;
BEGIN
delete from student;
select count(*) into student_count from student;
dbms_output.put(‘sql set count before :’);
dbms_output.put_line(student_count);
insert into student values (1001, ‘liumiaocn’);
insert into student values (1002, ‘liumiao’);
insert into student values (1003, ‘michael’);
select count(*) into student_count from student;
dbms_output.put(‘sql set count after :’);
dbms_output.put_line(student_count);
END;
/
exec addstudents();
oracle@e871d42341c0:~$

结果执行信息如下

oracle@e871d42341c0:~$ sqlplus system/liumiao123 <<EOF
set serveroutput on;
@/tmp/addstudent.sql
EOF
SQL*Plus: Release 11.2.0.2.0 Production on Mon Oct 22 04:42:11 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>
Procedure created.
sql set count before :0
sql set count after :3
PL/SQL procedure successfully completed.
SQL> Disconnected from Oracle Database 11g Express Edition Release 11.2.0.2.0 – 64bit Production
oracle@e871d42341c0:~$

接下来我们修改一下内容，使得第二行主键重复

oracle@e871d42341c0:~$ cat /tmp/addstudent.sql
create or replace PROCEDURE addstudents
IS
student_count number;
BEGIN
delete from student;
select count(*) into student_count from student;
dbms_output.put(‘sql set count before :’);
dbms_output.put_line(student_count);
insert into student values (1001, ‘liumiaocn’);
insert into student values (1001, ‘liumiao’);
insert into student values (1003, ‘michael’);
select count(*) into student_count from student;
dbms_output.put(‘sql set count after :’);
dbms_output.put_line(student_count);
END;
/
exec addstudents();
oracle@e871d42341c0:~$

再次执行，自然会出错，但是可以看到，正确报出了所在行数，这是procedure的机制提示的信息

oracle@e871d42341c0:~$ sqlplus system/liumiao123 <<EOF
set serveroutput on;
@/tmp/addstudent.sql
EOF
SQL*Plus: Release 11.2.0.2.0 Production on Mon Oct 22 04:44:25 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>
Procedure created.
sql set count before :0
BEGIN addstudents(); END;
*
ERROR at line 1:
ORA-00001: unique constraint (SYSTEM.SYS_C007024) violated
ORA-06512: at “SYSTEM.ADDSTUDENTS”, line 10
ORA-06512: at line 1
SQL> Disconnected from Oracle Database 11g Express Edition Release 11.2.0.2.0 – 64bit Production
oracle@e871d42341c0:~$

可以看到，ORA-06512: at “SYSTEM.ADDSTUDENTS”, line 10的信息就是我们期待的信息，提示出在这个存储过程的第10行执行出现问题，而实际可以使用dbms_utility.format_error_backtrace结合exception给出更为清晰地方式，比如：

oracle@e871d42341c0:~$ cat /tmp/addstudent.sql
create or replace PROCEDURE addstudents
IS
student_count number;
BEGIN
delete from student;
select count(*) into student_count from student;
dbms_output.put(‘sql set count before :’);
dbms_output.put_line(student_count);
insert into student values (1001, ‘liumiaocn’);
insert into student values (1001, ‘liumiao’);
insert into student values (1003, ‘michael’);
select count(*) into student_count from student;
dbms_output.put(‘sql set count after :’);
dbms_output.put_line(student_count);
exception
when others then
dbms_output.put(‘exception happend with line info : ‘);
dbms_output.put_line(dbms_utility.format_error_backtrace);
END;
/
exec addstudents();
oracle@e871d42341c0:~$

执行结果确认：

oracle@e871d42341c0:~$ sqlplus system/liumiao123 <<EOF
set serveroutput on;
@/tmp/addstudent.sql
EOF
SQL*Plus: Release 11.2.0.2.0 Production on Mon Oct 22 04:49:27 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>
Procedure created.
sql set count before :0
exception happend with line info : ORA-06512: at “SYSTEM.ADDSTUDENTS”, line 10
PL/SQL procedure successfully completed.
SQL> Disconnected from Oracle Database 11g Express Edition Release 11.2.0.2.0 – 64bit Production
oracle@e871d42341c0:~$

这样则可以看出能够比较清晰地进行错误的定位了，但是由于功能受限，所以实际使用场景仍然较为有限，但是定位存储过程的信息则可以使用dbms_utility.format_error_backtrace等进行确认。

小结

多行sql执行定位可以考虑拆成单行来确认，而存储过程则可结合format_error_backtrace等进行确认以提供问题出现的所在行号。

总结

在sqlplus中执行的sql出错之后应该如何处理和对应，多行sql语句或者存储过程的信息如何进行错误定位，这篇文章将结合实例进行简单地说明。

环境准备

使用Oracle的精简版创建docker方式的demo环境，详细可参看：

oracle@e871d42341c0:~$

结果执行信息如下

接下来我们修改一下内容，使得第二行主键重复

oracle@e871d42341c0:~$ cat /tmp/addstudent.sql
create or replace PROCEDURE addstudents
IS
student_count number;
BEGIN
delete from student;
select count(*) into student_count from student;
dbms_output.put(‘sql set count before :’);
dbms_output.put_line(student_count);
insert into student values (1001, ‘liumiaocn’);
insert into student values (1001, ‘liumiao’);
insert into student values (1003, ‘michael’);
select count(*) into student_count from student;
dbms_output.put(‘sql set count after :’);
dbms_output.put_line(student_count);
END;
/
exec addstudents();
oracle@e871d42341c0:~$

再次执行，自然会出错，但是可以看到，正确报出了所在行数，这是procedure的机制提示的信息

oracle@e871d42341c0:~$ cat /tmp/addstudent.sql
create or replace PROCEDURE addstudents
IS
student_count number;
BEGIN
delete from student;
select count(*) into student_count from student;
dbms_output.put(‘sql set count before :’);
dbms_output.put_line(student_count);
insert into student values (1001, ‘liumiaocn’);
insert into student values (1001, ‘liumiao’);
insert into student values (1003, ‘michael’);
select count(*) into student_count from student;
dbms_output.put(‘sql set count after :’);
dbms_output.put_line(student_count);
exception
when others then
dbms_output.put(‘exception happend with line info : ‘);
dbms_output.put_line(dbms_utility.format_error_backtrace);
END;
/
exec addstudents();
oracle@e871d42341c0:~$