outer_columns

datafusion_optimizer::optimize_projections

Function outer_columns 

Source 
fn outer_columns<'a>(expr: &'a Expr, columns: &mut HashSet<&'a Column>)
Expand description

Accumulates outer-referenced columns by the given expression, expr.

ยงParameters

  • expr - The expression to analyze for outer-referenced columns.
  • columns - A mutable reference to a HashSet<Column> where detected columns are collected.