Module datafusion_expr::expr_rewriter
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Expression rewriter
Traits§
- Trait for rewriting
Expr
s into function calls.
Functions§
- Returns plan with expressions coerced to types compatible with schema types
- Create a Column from the Scalar Expr
- Recursively call
Column::normalize_with_schemas
on allColumn
expressions in theexpr
expression tree. - See
Column::normalize_with_schemas_and_ambiguity_check
for usage - Recursively normalize all
Column
expressions in a list of expression trees - Recursively replace all
Column
expressions in a given expression tree withColumn
expressions provided by the hash map argument. - Rewrites
expr
usingrewriter
, ensuring that the output has the same name asexpr
prior to rewrite, adding an alias if necessary. - Rewrite sort on aggregate expressions to sort on the column of aggregate output For example,
max(x)
is written tocol("max(x)")
- Recursively remove all the [‘OuterReferenceColumn’] and return the inside Column in the expression tree.
- Recursively un-alias an expressions
- Recursively ‘unnormalize’ (remove all qualifiers) from an expression tree.
- Recursively un-normalize all
Column
expressions in a list of expression trees