docs/sql-manual/sql-functions/string-functions/replace_empty.md

---
{
    "title": "REPLACE_EMPTY",
    "language": "en"
}
---

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## replace_empty
### description
#### Syntax

Since 2.1.5

`VARCHAR REPLACE_EMPTY (VARCHAR str, VARCHAR old, VARCHAR new)`

Replace all `old` substrings in `str` string with `new` string.

Unlike the `REPLACE()` function, when `old` is an empty string, the `new` string is inserted before each character of the `str` string and at the end of the `str` string.

Other than that, the other behaviors are exactly the same as the `REPLACE()` function.

This function is mainly used for compatibility with Presto and Trino, and its behavior is exactly the same as the `REPLACE()` function in Presto and Trino.

### example

```
mysql> select replace_empty("http://www.baidu.com:9090", "9090", "");
+------------------------------------------------------+
| replace('http://www.baidu.com:9090', '9090', '') |
+------------------------------------------------------+
| http://www.baidu.com:                                |
+------------------------------------------------------+

mysql> select replace_empty("abc", '', 'xyz');
+---------------------------------+
| replace_empty('abc', '', 'xyz') |
+---------------------------------+
| xyzaxyzbxyzcxyz                 |
+---------------------------------+

mysql> select replace_empty("", "", "xyz");
+------------------------------+
| replace_empty('', '', 'xyz') |
+------------------------------+
| xyz                          |
+------------------------------+
```

### keywords

    REPLACE_EMPTY