OperatorMap type doesn't include $exists

[snigdha920]

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I have a deletedAt field in my entities. I'm trying to fetch the entities where the deletedAt field does not exist.

Here's what my query looks like:

await this.myRepository.findOneOrFail({deletedAt: {$exists: false}})

After MikroORM v5, I can't use this anymore.

It would be nice to have $exists option. Since it would check for both undefined and null at the same time. Also, there might be several other projects using $exists option, which will break. Having the $exists option will make v5 more backwards compatible with v4.

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Update the types of OperatorMap<T> to include $exists as well.

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await this.myRepository.findOneOrFail({deletedAt: undefined})

I find this a little wobbly, because it won't match deletedAt being set to null.

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I'd be happy to open a PR if you think this is worth adding.

[B4nan]

It was never there. In v4 it was just not strictly type checked.

After MikroORM v5, I can't use this anymore.

This is a TS error, you can just cast as any to get around it.

I dont mind adding it there, as long as we will have meaningful error handling for SQL drivers where this wont work (or maybe we should just contert that for SQL drivers to SQL alternative, maybe to foo is not null?)

[snigdha920]

It was never there. In v4 it was just not strictly type checked.

Right, that makes sense. My team tries to avoid any type as much as possible, so I'm going with the undefined approach.

I dont mind adding it there, as long as we will have meaningful error handling for SQL drivers where this wont work (or maybe we should just contert that for SQL drivers to SQL alternative, maybe to foo is not null?)

If I understood correctly, you are suggesting offering an equivalent $exists for SQL drivers instead of an error? I like that idea.

foo is not null

Matching MongoDB's exists, we can return all fields which are not equal to undefined.

[B4nan]

Matching MongoDB's exists, we can return all fields which are not equal to undefined.

In SQL there is no undefined value, the value of nullable column is always null even if you did not provide it. That's why I said foo is not null could be good enough equivalent for that.

[snigdha920]

Oh, I did not know that. In that case, what you said is perfect. Should I provide a PR for the same?