The IndexCreateStatement does not work with mysql, if the name is not provided

[mohs8421]

Description

When an IndexCreateStatement is not build with a name, the result in mysql will look like this:

CREATE INDEX  ON `table` (`col`)

That query will fail, because of the missing name.

Steps to Reproduce

1. Write an IndexCreateStatement, ommitting the name
2. Try to execute it

Suggested Solution

Use builder pattern to expect the name, table and col properties of the IndexCreateStatement to be present. See: https://crates.io/crates/derive_builder

Expected Behavior

It would be better if the creation of the IndexCreateStatement fails directly, best at compile time, so you cannot forget it. Same goes to providing a table and at least one column.

Actual Behavior

It fails at runtime when the query should be executed

Reproduces How Often

always

Workarounds

Remember to put everything in the first place

Versions

[tyt2y3]

Thank you for the suggestion. Does derive_builder support mandatory field?
I think such an API is possible, with a more complex type system. Basically, IndexBuilder -> IndexWithName -> IndexWithNameAndTable etc? I am worried about the compilation time / complexity with this approach.

[mohs8421]

I think it would be simpler to have the build() function return a result, as in the example of the derive_builder crate.
Yes, that would cause it to not fail at compile time, but at runtime, but at least before execution in sql.
I'm not sure whether this can be pushed to fail at compile time without writing a macro for that.

[billy1624]

I do remember there are builder pattern which enforce the checking at compile time. Here is one of them https://crates.io/crates/typed-builder

[mohs8421]

this looks like the best matching solution, might even be valuable for other use cases like other common statements.

[billy1624]

Hey @mohs8421, you wanna give it a try? :P

[mohs8421]

I would, but have quite some other issues that consume my time

[mohs8421]

I am currently playing with that, although I think regarding this current issue, I go back to a different approach - which is generating a name from the given information.

[billy1624]

Context for newcomers, related PR:

• Resolving IndexCreateStatement not generating a valid query when no name is provided sea-query#638