Hi everyone,
I'd like to issue a LIMIT for a DELETE statement.
By default, this is not possible as far as I can see it. The function limit() is available for SELECT in general however.
Searching through documentation, I found a reference to with_dialect_option():
https://docs.sqlalchemy.org/en/20/search.html?q=with_dialect_options&check_keywords=yes&area=default#
Which points to https://docs.sqlalchemy.org/en/20/core/dml.html#sqlalchemy.sql._expression_.UpdateBase.with_dialect_options claiming the function to be available in UpdateBase (although the documentation off given the claimed method is not callable like documented). This was the case in 1.4 (https://github.com/sqlalchemy/sqlalchemy/blob/rel_1_4/lib/sqlalchemy/sql/dml.py#L345) already and also in 2.0 (https://github.com/sqlalchemy/sqlalchemy/blob/main/lib/sqlalchemy/sql/dml.py#L438).
However, trying to call it as per documentation results in an exception being raised:
```
sqlalchemy.exc.ArgumentError: Argument 'mysql_limit' is not accepted by dialect 'mysql' on behalf of <class 'sqlalchemy.sql.dml.Delete'>
```
This is caused by https://github.com/sqlalchemy/sqlalchemy/blob/main/lib/sqlalchemy/dialects/mysql/base.py#L2454 not listing sql.Delete explicitly. UpdateBase apparently cannot be referenced either given the import (guessing as it's not imported explicitly in https://github.com/sqlalchemy/sqlalchemy/blob/main/lib/sqlalchemy/sql/__init__.py or not referenced another way?).
However, by adding Delete just like Update will have the following line run fine without an error - but not adding the LIMIT either. My best guess right now would be due to the lack of limit clause handling?
```
stmt = stmt.with_dialect_options(mysql_limit=limit, mariadb_limit=limit)
```
where `limit` simply is an integer.
Any hints or help is appreciated. I can also raise a ticket on Github :)
Best regards
--
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