Error handling of query (constraints, SQLite)

[AxelMontini]

This is both a SQL and SQLx question.
I'm writing a server that must know whether a query failed due to a constraint violation or an unknown cause.
The database is SQLite.

CREATE TABLE Items (
  shelf INTEGER NOT NULL,
  ...,
  UNIQUE(shelf)
);

Let's say that a table contains items which are placed on a shelf each.
When trying to place an item a shelf x, an error occurs because there's already an item there.

I'm struggling to find a way to find out whether the query failed because the planets have aligned or simply because x is not UNIQUE.

I saw a constraint function on DatabaseError, but it's limited to PG.

I don't know if this is even possible, or if I shouldn't do this in the first place.

Any suggestions?

[mehcode]

The .code() method on SqliteError should return "2067" for a unique failure. You can't get the exact constraint name with sqlite but you'll at least know its because of a unique constraint.

See https://www.sqlite.org/rescode.html for more codes. It could make sense to have a SqliteErrorKind like std::io::ErrorKind to enum those.

[AxelMontini]

Thank you, that could work.
I will either try using the constants provided by libsqlite3-sys or simply define my own.