docs/sql-manual/sql-functions/ip-functions/is-ipv4-string.md

---
{
"title": "IS_IPV4_STRING",
"language": "en"
}
---

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## IS_IPV4_STRING

IS_IPV4_STRING

### Description

#### Syntax

`BOOLEAN IS_IPV4_STRING(STRING ipv4_str)`

Receive an IPv4 address in the form of a string as a parameter. If it is a correctly formatted and valid IPv4 address, return true; On the contrary, return false.

#### Notice

`If the input parameter is NULL, return NULL, indicating invalid input`

### Example

```sql
mysql> select is_ipv4_string(NULL);
+----------------------+
| is_ipv4_string(NULL) |
+----------------------+
|                 NULL |
+----------------------+

mysql> CREATE TABLE `test_is_ipv4_string` (
      `id` int,
      `ip_v4` string
    ) ENGINE=OLAP
    DISTRIBUTED BY HASH(`id`) BUCKETS 4
    PROPERTIES (
    "replication_allocation" = "tag.location.default: 1"
    );
    
mysql> insert into test_is_ipv4_string values(0, NULL), (1, '0.0.0.'), (2, ''), (3, '.'), (4, '255.255.255.255');

mysql> select id, is_ipv4_string(ip_v4) from test_is_ipv4_string order by id;
+------+-----------------------+
| id   | is_ipv4_string(ip_v4) |
+------+-----------------------+
|    0 |                  NULL |
|    1 |                     0 |
|    2 |                     0 |
|    3 |                     0 |
|    4 |                     1 |
+------+-----------------------+
```

### Keywords

IS_IPV4_STRING, IP