return Result<> from lf_sql

lib/explorer/polars_backend/lazy_frame.ex

@@ -583,9 +583,13 @@ defmodule Explorer.PolarsBackend.LazyFrame do
 
   @impl true
   def sql(ldf, sql_string, table_name) do
-    ldf.data
-    |> Native.lf_sql(sql_string, table_name)
-    |> Shared.create_dataframe()
+    with {:ok, polars_lf} <- Native.lf_sql(ldf.data, sql_string, table_name),
+         {:ok, names} <- Native.lf_names(polars_lf),
+         {:ok, dtypes} <- Native.lf_dtypes(polars_lf) do
+      Explorer.Backend.DataFrame.new(polars_lf, names, dtypes)
+    else
+      {:error, polars_error} -> raise polars_error
+    end
   end
 
   @impl true

native/explorer/src/lazyframe.rs

@@ -346,12 +346,18 @@ pub fn lf_concat_columns(
 }
 
 #[rustler::nif]
-pub fn lf_sql(lf: ExLazyFrame, sql_string: &str, table_name: &str) -> ExLazyFrame {
+pub fn lf_sql(
+    lf: ExLazyFrame,
+    sql_string: &str,
+    table_name: &str,
+) -> Result<ExLazyFrame, ExplorerError> {
     let mut ctx = polars::sql::SQLContext::new();
 
     let lf = lf.clone_inner();
     ctx.register(table_name, lf);
 
-    let lf_sql = ctx.execute(sql_string).unwrap();
-    ExLazyFrame::new(lf_sql)
+    match ctx.execute(sql_string) {
+        Ok(lf_sql) => Ok(ExLazyFrame::new(lf_sql)),
+        Err(polars_error) => Err(ExplorerError::Polars(polars_error)),
+    }
 }