xuzifu666 commented on code in PR #4939:
URL: https://github.com/apache/calcite/pull/4939#discussion_r3238664646
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site/_docs/reference.md:
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@@ -244,9 +244,14 @@ starWithExclude:
*
| * EXCLUDE '(' column [, column ]* ')'
+starWithReplace:
+ *
+ | * REPLACE '(' expression AS column [, expression AS column ]* ')'
+
Note:
* `SELECT * EXCLUDE (...)` is recognized only when the Babel parser is
enabled. It sets the generated parser configuration flag `includeStarExclude`
to `true` (the standard parser leaves that flag `false`), which allows a `STAR`
token followed by `EXCLUDE` (or the alias `EXCEPT`) and a parenthesized
identifier list to be parsed into a `SqlStarExclude` node and ensures
validators respect the exclusion list when expanding the projection. Reusing
the same parser configuration elsewhere enables the same syntax for other
components that need it.
+* `SELECT * REPLACE (...)` is recognized only when the Babel parser is
enabled. It sets the generated parser configuration flag `includeStarReplace`
to `true` (the standard parser leaves that flag `false`), which allows a `STAR`
token followed by `REPLACE` and a parenthesized list of `expression AS column`
pairs to be parsed into a `SqlStarReplace` node and ensures validators
substitute the specified expressions for the matching columns when expanding
the projection. The column alias must either be a simple identifier or, for a
table-qualified star such as `t.*`, a qualified identifier whose prefix matches
the star's table alias. Reusing the same parser configuration elsewhere enables
the same syntax for other components that need it.
Review Comment:
I did some changes here to make it more clear.
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