MySQL基础：搭建bc网站sql执行错误时的控制方式
行语句的正常执行
搭建bc网站q<277.03.4.83.6>
比如执行多条正常执行的语句，示例命令如下所示：
select version();
select "Hello LiuMiao" as "Greetings";
select 20+22 as Result;
使用HereDocument方式执行如下所示：
liumiaocn:~ liumiao$ mysql -uroot -proot <
> select version();
> select "Hello LiuMiao" as "Greetings";
> select 20+22 as Result;
> EOF
mysql: [Warning] Using a password on the command line interface can be insecure.
version()
8.0.11
Greetings
Hello LiuMiao
Result
42
liumiaocn:~ liumiao$
多行语句中间出错时的缺省动作
Oracle多行语句执行出错时在sqlplus中会继续执行，而在mysql控制台中会怎样呢？我们可以在上述语句中添加一行错误的语法或者命令来进行验证：
mysql -uroot -proot <
select version();
errorcommand;
select "Hello LiuMiao" as "Greetings";
select 20+22 as Result;
EOF
执行结果如下所示
liumiaocn:~ liumiao$ mysql -uroot -proot <
> select version();
> errorcommand;
> select "Hello LiuMiao" as "Greetings";
> select 20+22 as Result;
> EOF
mysql: [Warning] Using a password on the command line interface can be insecure.
version()
8.0.11
ERROR 1064 (42000) at line 2: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'errorcommand' at line 1
liumiaocn:~ liumiao$
可以看到，缺省情况下碰到错误就停下来了。
WHENEVER SQLERROR
在oracle中通过WHENEVER SQLERROR来进行控制。语法如下所示
WHENEVER SQLERROR {EXIT [SUCCESS | FAILURE | WARNING | n | variable | :BindVariable] [COMMIT | ROLLBACK] | CONTINUE [COMMIT | ROLLBACK | NONE]}
