fix: make the order of sort key deterministic

internal_types/src/schema/sort.rs

@@ -147,7 +147,7 @@ impl<'a> SortKey<'a> {
         self.columns.is_empty()
     }
 
-    /// Returns sort keys of the given columns
+    /// Returns a subset of the sort key that includes only the given columns
     pub fn selected_sort_key(&self, select_keys: Vec<&str>) -> SortKey<'a> {
         let keys: IndexMap<&'a str, SortOptions> = self
             .columns

query/src/lib.rs

@@ -211,13 +211,10 @@ pub fn compute_sort_key<'a>(summaries: impl Iterator<Item = &'a TableSummary>) -
     }
 
     trace!(cardinalities=?cardinalities, "cardinalities of of columns to compute sort key");
-    print!(
-        "cardinalities of of columns to compute sort key: {:#?}",
-        cardinalities
-    );
 
     let mut cardinalities: Vec<_> = cardinalities.into_iter().collect();
-    cardinalities.sort_by_key(|x| x.1);
+    // Sort by (cardinality, column_name) to have deterministic order if same cardinality
+    cardinalities.sort_by_key(|x| (x.1, x.0));
 
     let mut key = SortKey::with_capacity(cardinalities.len() + 1);
     for (col, _) in cardinalities {
@@ -226,7 +223,6 @@ pub fn compute_sort_key<'a>(summaries: impl Iterator<Item = &'a TableSummary>) -
     key.push(TIME_COLUMN_NAME, Default::default());
 
     trace!(computed_sort_key=?key, "Value of sort key from compute_sort_key");
-    println!("Value of sort key from compute_sort_key: {:#?}", key);
 
     key
 }

src/influxdb_ioxd/http.rs

@@ -1123,7 +1123,7 @@ mod tests {
     async fn test_query_json() {
         let (client, server_url) = setup_test_data().await;
 
-        // send a second line of data to demontrate how that works
+        // send a second line of data to demonstrate how that works
         let lp_data =
             "h2o_temperature,location=Boston,state=MA surface_degrees=50.2 1617286224000000000";