6.6 判断字符串是不是字母类型的

生成测试数据

create view v as
select ename as data from emp where deptno=10 union all
select concat(ename,', $',sal,'.00') as data from emp where deptno=20 union all
select concat(ename,deptno) as data from emp where deptno=30;

mysql> select * from v;
+----------+
| data     |
+----------+
| CLARK    |
| KING     |
| MILLER   |
| ALLEN30  |
| WARD30   |
| MARTIN30 |
| BLAKE30  |
| TURNER30 |
| JAMES30  |
+----------+

解决方案：

mysql> select data from v
where data regexp '[^0-9a-zA-Z]' = 0 ;
+----------+
| data     |
+----------+
| CLARK    |
| KING     |
| MILLER   |
| ALLEN30  |
| WARD30   |
| MARTIN30 |
| BLAKE30  |
| TURNER30 |
| JAMES30  |
+----------+