[GitHub] [pinot] amrishlal commented on a change in pull request #7959: [7867] Handle Select * with Extra Columns

[GitBox <gi...@apache.org>]

amrishlal commented on a change in pull request #7959:
URL: https://github.com/apache/pinot/pull/7959#discussion_r792914494



##########
File path: pinot-broker/src/main/java/org/apache/pinot/broker/requesthandler/BaseBrokerRequestHandler.java
##########
@@ -1487,6 +1498,46 @@ static void updateColumnNames(String rawTableName, PinotQuery pinotQuery, boolea
     }
   }
 
+  private static void expandStarExpressionToActualColumns(PinotQuery pinotQuery, Map<String, String> columnNameMap,
+      Expression selectStarExpr) {
+    List<Expression> originalSelections = pinotQuery.getSelectList();
+    // Avoid using stream apis in query path because we have found that it has poorer performance compared to
+    // regular apis.
+    Set<String> originallySelectedColumnNames = new HashSet<>();
+    for (Expression originalSelection : originalSelections) {
+      if (originalSelection.isSetIdentifier()) {
+        originallySelectedColumnNames.add(originalSelection.getIdentifier().getName());
+      }
+    }
+    List<Expression> newSelections = new ArrayList<>();
+    for (Expression selection : originalSelections) {
+      if (selection.equals(selectStarExpr)) {
+        //expand '*' to actual columns, exclude default virtual columns
+        for (String tableCol : columnNameMap.values()) {
+          //we exclude default virtual columns and those columns that are already a part of originalSelections (to
+          // dedup columns that are selected multiple times)

Review comment:
       So by extension, `SELECT *, * FROM baseballStats` should also be deduped right?




-- 
This is an automated message from the Apache Git Service.
To respond to the message, please log on to GitHub and use the
URL above to go to the specific comment.

To unsubscribe, e-mail: commits-unsubscribe@pinot.apache.org

For queries about this service, please contact Infrastructure at:
users@infra.apache.org



---------------------------------------------------------------------
To unsubscribe, e-mail: commits-unsubscribe@pinot.apache.org
For additional commands, e-mail: commits-help@pinot.apache.org