Add CAST expression support to parser#3207
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@Fokko @geruh @kevinjqliu PTAL |
| expected = EqualTo( | ||
| UnboundTransform(Reference("created_at"), DayTransform()), | ||
| StringLiteral("2024-01-01"), | ||
| ) |
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For testing, I think it would be good to have an integration test as well. The StringLiteral should be converted to a DateLiteral when bound to the transform.
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Added a unit test for this.
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I've been playing around with this PR and I ran into something. Here's a quick demo script for your own testing. One row, 1/1/24, we'd expect to be able to query it in this script. It looks like we're running into this issue because we coerce ts to a TimestampType at comparison time. That means the right side is |
| assert expected == parser.parse("CAST(created_at AS date) = '2024-01-01'") | ||
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| def test_cast_date_binds_string_literal_to_date() -> None: |
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We should have more tests like this with uneven types. I posted an example in another comment.
3 participants
Closes #198
Picks up where #209 left off with @Fokko's feedback addressed. Thanks @jayceslesar for the original work.
Rationale for this change
Adds
CAST(column AS type)parsing that maps to Iceberg transforms (date→DayTransform,year→YearTransform,month→MonthTransform,hour→HourTransform). Also implementsBoundTransform.ref()andeval()— both were missing abstract methods required byBoundTerm. IntroducesUnboundTransformwithbind()that validates viacan_transform().Are these changes tested?
Yes. 11 new tests covering all transform types, case insensitivity, nested fields, unsupported types, comparison operators, and boolean composition.
Are there any user-facing changes?
No.