WIP: Expr support getfield #392
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timgraham
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| expr = { | ||
| "$expr": { | ||
| "$gt": [ | ||
| {"$getField": {"input": "$price", "field": "value"}}, |
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Can we optimize this down to remove the $getField when the field names don't contain $ or .? Something like:
{
"$match": {
"$expr": {
"$gt": ["$price.value", "$discounted_price.value"]
}
}
}
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We could. I'm trying to think if there's any case where this would be an issue if it mistakenly resolved it.
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This would have to be a two-phase conversion. I think it may even be best to still change it in our actual query code.
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I'm assuming here that this change ends up being needed. Holding off until we either get customer complaints or the refactor can't solve this makes more sense to me for now.
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Yeah, I tried to make it work (and I think I managed to), but the silent mutation of $getField to $field is worrying to me. Even if I manage to make things pass tests, it just feels out of scope of the optimizers goal, which is to explicitly change things from $expr to $match.
TODO