add note

Signed-off-by: tison <[email protected]>

sqlx-postgres/src/types/mod.rs

@@ -157,7 +157,7 @@
 //!
 //! # [Enumerations](https://www.postgresql.org/docs/current/datatype-enum.html)
 //!
-//! User-defined enumerations are supported through a derive for `Type`.
+//! User-defined enumerations are supported through a `derive` for `Type`.
 //!
 //! ```text
 //! CREATE TYPE mood AS ENUM ('sad', 'ok', 'happy');
@@ -187,6 +187,10 @@
 //! #[sqlx(type_name = "text")]
 //! enum Mood { Sad, Ok, Happy }
 //! ```
+//!
+//! Note that an error can occur if you attempt to decode a value not contained within the enum
+//! definition.
+//!
 
 use crate::type_info::PgTypeKind;
 use crate::{PgTypeInfo, Postgres};