> 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/schema/pg-prefix-is-reserved-for-system-schemas.md).

# pg Prefix Is Reserved For System Schemas

Have you ever tried to create a schema with `pg_` as the first part of the name of the schema? If so, you probably didn't get very far. Postgres won't let you do that. It reserves the `pg_` prefix for system schemas. If you try to create a schema in this way, you'll get an *unacceptable schema name* error.

```sql
> create schema pg_cannot_do_this;
ERROR:  unacceptable schema name "pg_cannot_do_this"
DETAIL:  The prefix "pg_" is reserved for system schemas.
```
