Function add_filter

datafusion/expr/src/utils.rs:1239–1252

Returns a new [LogicalPlan] that filters the output of `plan` with a [LogicalPlan::Filter] with all `predicates` ANDed. # Example Before: ```text plan ``` After: ```text Filter(predicate) plan ```

(plan: LogicalPlan, predicates: &[&Expr])

///   plan
/// ```
pub fn add_filter(plan: LogicalPlan, predicates: &[&Expr]) -> Result<LogicalPlan> {
    // reduce filters to a single filter with an AND
    let predicate = predicates
        .iter()
        .skip(1)
        .fold(predicates[0].clone(), |acc, predicate| {
            and(acc, (*predicate).to_owned())
        });

    Ok(LogicalPlan::Filter(Filter::try_new(
        predicate,
        Arc::new(plan),
    )?))
}

/// Looks for correlating expressions: for example, a binary expression with one field from the subquery, and
/// one not in the subquery (closed upon from outer scope)