Method evaluate

datafusion/physical-expr/src/expressions/case.rs:1318–1340

(&self, batch: &RecordBatch)

    }

    fn evaluate(&self, batch: &RecordBatch) -> Result<ColumnarValue> {
        match &self.eval_method {
            EvalMethod::WithExpression(p) => {
                // this use case evaluates "expr" and then compares the values with the "when"
                // values
                self.case_when_with_expr(batch, p)
            }
            EvalMethod::NoExpression(p) => {
                // The "when" conditions all evaluate to boolean in this use case and can be
                // arbitrary expressions
                self.case_when_no_expr(batch, p)
            }
            EvalMethod::InfallibleExprOrNull => {
                // Specialization for CASE WHEN expr THEN column [ELSE NULL] END
                self.case_column_or_null(batch)
            }
            EvalMethod::ScalarOrScalar => self.scalar_or_scalar(batch),
            EvalMethod::ExpressionOrExpression(p) => self.expr_or_expr(batch, p),
            EvalMethod::WithExprScalarLookupTable(lookup_table) => {
                self.with_lookup_table(batch, lookup_table)
            }
        }
    }

    fn children(&self) -> Vec<&Arc<dyn PhysicalExpr>> {
        let mut children = vec![];