Function extract_string_literal

datafusion/pruning/src/pruning_predicate.rs:1811–1817

(expr: &Arc<dyn PhysicalExpr>)

}

fn extract_string_literal(expr: &Arc<dyn PhysicalExpr>) -> Option<&str> {
    if let Some(lit) = expr.downcast_ref::<phys_expr::Literal>() {
        let s = unpack_string(lit.value())?;
        return Some(s);
    }
    None
}

/// Convert `column LIKE literal` where P is a constant prefix of the literal
/// to a range check on the column: `P <= column && column < P'`, where P' is the