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@alamb alamb commented Apr 23, 2024

Which issue does this PR close?

Part of #9637

Rationale for this change

While working on #10039 I saw a few copies that could be avoided that are independent of the larger refactor (which is proving trickier than I had hoped)

What changes are included in this PR?

  1. Remove some unnecessary clones in ExprRewriter (these are pretty minor in the grand scheme of things)

Are these changes tested?

Existing CI

Are there any user-facing changes?

@github-actions github-actions bot added the optimizer Optimizer rules label Apr 23, 2024
/// See the module level documentation for more detail on coercion.
fn coerce_arguments_for_signature(
expressions: &[Expr],
expressions: Vec<Expr>,
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this will stop all the arguments to function calls being copied, which seems good

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I always thought having less possible coercible type is preferred 🤔

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I am not sure what you mean

Perhaps you are referring to preferring &[Expr] over &Vec<Expr>? If so the difference here is that the Vec was owned (and thus we don't have to copy the contents via to_vec())

if let DataType::FixedSizeList(field, _) = data_type {
let field = field.as_ref().clone();
let to_type = DataType::List(Arc::new(field));
let to_type = DataType::List(field.clone());
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FieldRef is an Arc<Field> -- so this clone is just an Arc::clone (rather than copying the entire filed)

}

/// Cast `expr` to the specified type, if possible
fn cast_expr(expr: &Expr, to_type: &DataType, schema: &DFSchema) -> Result<Expr> {
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This function just wrapped Expr::cast_to in an API that forced a clone, so I removed it

@alamb alamb marked this pull request as ready for review April 23, 2024 19:41
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👍

@Dandandan Dandandan merged commit deebda7 into apache:main Apr 24, 2024
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Thank you @alamb

@alamb alamb deleted the alamb/chipping_away branch April 24, 2024 10:50
ccciudatu pushed a commit to hstack/datafusion that referenced this pull request Apr 26, 2024
* Remove some clone in TypeCoercion

* Less clone

* less copy
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4 participants