# Inverse, Concate
__*CONCAT function*__
__*CANCAT_WS function*__
__*REVERSE function*__
+ `CONCAT(), CONCAT_WS()`: Concatenates the given parameters into a string
+ `REVERSE()`: Returns a string with the characters in reverse order
+ For example: 
  + `SELECT reverse('placeholder'), concat('hello ','world'), concat_ws(':','pingcap','cmg','pe');`  
```
tidb> SELECT reverse('placeholder'), concat('hello ','world'), concat_ws('~!@:@!~','pingcap','cmg','pe');
+------------------------+--------------------------+-------------------------------------+
| reverse('placeholder') | concat('hello ','world') | concat_ws(':','pingcap','cmg','pe') |
+------------------------+--------------------------+-------------------------------------+
| redlohecalp            | hello world              | pingcap:cmg:pe                      |
+------------------------+--------------------------+-------------------------------------+
1 row in set (0.00 sec)
```

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- CONCAT () return the concatenated string
- CONCAT_WS () return a string concatenated by a delimiter