Snowflake: Fix COPY INTO transformation parsing for cast expressions#2328
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97nitt wants to merge 3 commits intoapache:mainfrom
Open
Snowflake: Fix COPY INTO transformation parsing for cast expressions#232897nitt wants to merge 3 commits intoapache:mainfrom
97nitt wants to merge 3 commits intoapache:mainfrom
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…NTO transformation
iffyio
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Apr 29, 2026
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| // Snowflake `COPY INTO` transformation lists support casts like | ||
| // `$1:"col"::TYPE` and `$1::TYPE`. These are distinct from the bare | ||
| // `$<n>[.<col>][:<elem>]` stage-load-select-item shape, so the parser | ||
| // must fall through to the generic select-item parser to handle the | ||
| // `::` cast operator. | ||
| // | ||
| // Regression: the Snowflake-specific parser used to successfully | ||
| // consume `$1:"col"` as a stage-load-select-item, leaving `::TYPE` | ||
| // behind and causing "Expected: FROM, found: ::" once the COPY INTO | ||
| // body tried to expect `FROM`. |
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Suggested change
| // Snowflake `COPY INTO` transformation lists support casts like | |
| // `$1:"col"::TYPE` and `$1::TYPE`. These are distinct from the bare | |
| // `$<n>[.<col>][:<elem>]` stage-load-select-item shape, so the parser | |
| // must fall through to the generic select-item parser to handle the | |
| // `::` cast operator. | |
| // | |
| // Regression: the Snowflake-specific parser used to successfully | |
| // consume `$1:"col"` as a stage-load-select-item, leaving `::TYPE` | |
| // behind and causing "Expected: FROM, found: ::" once the COPY INTO | |
| // body tried to expect `FROM`. |
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| // `$1:"col"::NUMBER(38,0)`), not a stage-load-select-item. Bail so | ||
| // `maybe_parse` rewinds and the caller falls through to | ||
| // `parse_select_item`, which handles the cast correctly. |
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Suggested change
| // `$1:"col"::NUMBER(38,0)`), not a stage-load-select-item. Bail so | |
| // `maybe_parse` rewinds and the caller falls through to | |
| // `parse_select_item`, which handles the cast correctly. | |
| // `$1:"col"::NUMBER(38,0)`), not a stage-load-select-item. |
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| // Mix with an ordinary stage-load-select-item in the same list, | ||
| // so we don't over-correct and break the existing shape. |
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| // Mix with an ordinary stage-load-select-item in the same list, | |
| // so we don't over-correct and break the existing shape. |
iffyio
reviewed
Apr 29, 2026
| ), | ||
| ]; | ||
| for sql in variants { | ||
| snowflake().parse_sql_statements(sql).unwrap_or_else(|e| { |
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these should use verified_stmt?
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Summary
Snowflake
COPY INTO ... FROM (SELECT ...)transformation lists support castexpressions like
$1:"col"::TYPEand$1::TYPE, e.g.:Today the Snowflake-specific stage-load-select-item parser successfully
consumes
$1:"A"as a stage-load-select-item, leaves::NUMBER(38, 0)inthe token stream, and the surrounding
COPY INTObody then fails withExpected: FROM, found: ::.Changes
parse_select_item_for_data_load: bail (somaybe_parserewinds and thecaller falls through to the generic
parse_select_item) when the nexttoken is
::. The generic path already handles cast operators on$<n>references correctly.
$1:"col"::TYPE,$1::TYPE,$1:SEQUENCE::TYPE, multi-column lists, and a mixed list combining aplain stage-load-select-item with a cast item — verifying we don't
over-correct and break the existing shape.
Test plan
cargo testcargo fmt --checkcargo clippy --all-targets --all-features -- -D warnings