> For the complete documentation index, see [llms.txt](https://ploegert.gitbook.io/til/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://ploegert.gitbook.io/til/programmy/linux/is-app-installed/types-and-operators/generate-a-uuid.md).

# Generate A UUID

Postgres has support for universally unique identifiers (UUIDs) as a column data type via `uuid`. If you have a UUID column, you may need to generate a UUID. This requires the `uuid-ossp` module. This module provides a number of functions for generating UUIDs including the `uuid_generate_v4()` function which bases the UUID entirely off random numbers.

```sql
> create extension "uuid-ossp";
CREATE EXTENSION
> select uuid_generate_v4();
           uuid_generate_v4
--------------------------------------
 a0eebc99-9c0b-4ef8-bb6d-6bb9bd380a11
```

See the [postgres docs](http://www.postgresql.org/docs/9.4/static/uuid-ossp.html) for more details on UUID generation functions.