datafusion_python::datafusion_expr::utils

Function columnize_expr

Source 
pub fn columnize_expr(
    e: Expr,
    input: &LogicalPlan,
) -> Result<Expr, DataFusionError>
Expand description

Convert an expression into Column expression if it’s already provided as input plan.

For example, it rewrites:

.aggregate(vec![col("c1")], vec![sum(col("c2"))])?
.project(vec![col("c1"), sum(col("c2"))?

Into:

.aggregate(vec![col("c1")], vec![sum(col("c2"))])?
.project(vec![col("c1"), col("SUM(c2)")?