Add select key
```
- CREATE ENCRYPTKEY key_name AS "key_string"
- select key my_key
+-----------------------------+
| encryptKeyRef('', 'my_key') |
+-----------------------------+
| ABCD123456789 |
+-----------------------------+
```
Add select key
```
- CREATE ENCRYPTKEY key_name AS "key_string"
- select key my_key
+-----------------------------+
| encryptKeyRef('', 'my_key') |
+-----------------------------+
| ABCD123456789 |
+-----------------------------+
```