From bc015ef6ef8ea86ee3d7563169070131b75d9957 Mon Sep 17 00:00:00 2001
From: feiniaofeiafei <moailing@selectdb.com>
Date: Wed, 26 Mar 2025 14:32:30 +0800
Subject: [PATCH] [fix](nereids) EliminateGroupByConstant should replace agg's
 group by after removing constant group by keys (#49473)
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### What problem does this PR solve?

Issue Number: close #xxx

Related PR: #xxx

Problem Summary:

### Release note
```sql
 SELECT
    IF(
        t.`gender` IN ('女'),
        (
            TIMESTAMPDIFF(
                YEAR,
                NOW(),
                NOW()
            )
        ),
        1
    ) AS x0,
    TIMESTAMPDIFF(
        YEAR,
        NOW(),
        NOW()
    ) AS x1
FROM
t1 AS t
GROUP BY
    x0,
    x1;
```
after EliminateGroupByConstant, this sql will be rewritten to
```sql
 SELECT
    IF(
        t.`gender` IN ('女'),
        0,
        1
    ) AS x0,
    0 AS x1
FROM
t1 AS t
GROUP BY
     IF(
        t.`gender` IN ('女'),
        (
            TIMESTAMPDIFF(
                YEAR,
                NOW(),
                NOW()
            )
        ),
        1
    ) ;
```
The select expression and the group by expression is different, and will
report error in normalizeagg.
This pr changes using the foldmap rewrite the group by expresssion, and
after change the sql after EliminateGroupByConstant become:
```sql
 SELECT
    IF(
        t.`gender` IN ('女'),
        0,
        1
    ) AS x0,
    0 AS x1
FROM
t1 AS t
GROUP BY
     IF(
        t.`gender` IN ('女'),
        0,
        1
    ) ;
```
the select expression and the group by expression becomes same.
---
 .../analysis/EliminateGroupByConstant.java    |  5 ++--
 .../aggregate_groupby_constant.groovy         | 26 +++++++++++++++++++
 2 files changed, 29 insertions(+), 2 deletions(-)

diff --git a/fe/fe-core/src/main/java/org/apache/doris/nereids/rules/analysis/EliminateGroupByConstant.java b/fe/fe-core/src/main/java/org/apache/doris/nereids/rules/analysis/EliminateGroupByConstant.java
index 7f7e229da319f4..a58d98ff1217bd 100644
--- a/fe/fe-core/src/main/java/org/apache/doris/nereids/rules/analysis/EliminateGroupByConstant.java
+++ b/fe/fe-core/src/main/java/org/apache/doris/nereids/rules/analysis/EliminateGroupByConstant.java
@@ -27,8 +27,8 @@
 import org.apache.doris.nereids.trees.plans.Plan;
 import org.apache.doris.nereids.trees.plans.logical.LogicalAggregate;
 import org.apache.doris.nereids.util.ExpressionUtils;
+import org.apache.doris.nereids.util.Utils;
 
-import com.google.common.collect.ImmutableList;
 import com.google.common.collect.Sets;
 
 import java.util.HashMap;
@@ -75,7 +75,8 @@ public Rule build() {
             if (slotGroupByExprs.isEmpty() && lit != null) {
                 slotGroupByExprs.add(lit);
             }
-            return aggregate.withGroupByAndOutput(ImmutableList.copyOf(slotGroupByExprs),
+            return aggregate.withGroupByAndOutput(
+                    ExpressionUtils.replace(Utils.fastToImmutableList(slotGroupByExprs), constantExprsReplaceMap),
                     ExpressionUtils.replaceNamedExpressions(outputExprs, constantExprsReplaceMap));
         }).toRule(RuleType.ELIMINATE_GROUP_BY_CONSTANT);
     }
diff --git a/regression-test/suites/nereids_p0/aggregate/aggregate_groupby_constant.groovy b/regression-test/suites/nereids_p0/aggregate/aggregate_groupby_constant.groovy
index 9b1f186a4cc5eb..bbc3cd8a72ae46 100644
--- a/regression-test/suites/nereids_p0/aggregate/aggregate_groupby_constant.groovy
+++ b/regression-test/suites/nereids_p0/aggregate/aggregate_groupby_constant.groovy
@@ -18,6 +18,7 @@
 suite("aggregate_groupby_constant") {
     sql "SET enable_nereids_planner=true"
     sql "SET enable_fallback_to_original_planner=false"
+    sql "set disable_nereids_rules='prune_empty_partition'"
 
     sql """ DROP TABLE IF EXISTS table_500_undef_partitions2_keys3_properties4_distributed_by5; """
     sql """
@@ -47,4 +48,29 @@ suite("aggregate_groupby_constant") {
                     OR table1 . `col_int_undef_signed` <> NULL )
             GROUP BY  field1,field2
             ORDER BY  field1,field2 LIMIT 10000;"""
+
+    sql """
+        SELECT
+            IF(
+                t.`col_varchar_10__undef_signed` IN ('女'),
+                (
+                    TIMESTAMPDIFF(
+                        YEAR,
+                        NOW(),
+                        NOW()
+                    )
+                ),
+                1
+            ) AS x0,
+            TIMESTAMPDIFF(
+                YEAR,
+                NOW(),
+                NOW()
+            ) AS x1
+        FROM
+        table_500_undef_partitions2_keys3_properties4_distributed_by5 AS t
+        GROUP BY
+            x0,
+            x1;
+    """
 }