[GitHub] [doris] morrySnow commented on a diff in pull request #15530: [fix](nereids)support nulls first/last in order by clause

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

morrySnow commented on code in PR #15530:
URL: https://github.com/apache/doris/pull/15530#discussion_r1059459698


##########
fe/fe-core/src/main/antlr4/org/apache/doris/nereids/DorisParser.g4:
##########
@@ -166,7 +166,7 @@ sortClause
     ;
 
 sortItem
-    :  expression ordering = (ASC | DESC)?
+    :  expression ordering = (ASC | DESC)? ( NULLS FIRST | NULLS LAST )?

Review Comment:
   nit:
   ```suggestion
       :  expression ordering = (ASC | DESC)? (NULLS (LAST | FIRST))?
   ```



##########
fe/fe-core/src/main/java/org/apache/doris/nereids/parser/LogicalPlanBuilder.java:
##########
@@ -1076,8 +1076,7 @@ public List<String> visitIdentifierSeq(IdentifierSeqContext ctx) {
     public OrderKey visitSortItem(SortItemContext ctx) {
         return ParserUtils.withOrigin(ctx, () -> {
             boolean isAsc = ctx.DESC() == null;
-            // TODO(wj): isNullFirst
-            boolean isNullFirst = true;
+            boolean isNullFirst = !(ctx.NULLS() != null && ctx.LAST() != null);

Review Comment:
   nit:
   ```suggestion
               boolean isNullFirst = ctx.LAST() == null;
   ```



-- 
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@doris.apache.org

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


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