[BugFix] Fix incorrect execution plan when generated column rewrite i…

…n join relation if left table and right table has the same column name (#52584)

Signed-off-by: srlch <[email protected]>

fe/fe-core/src/main/java/com/starrocks/qe/SessionVariable.java

@@ -769,6 +769,8 @@ public static MaterializedViewRewriteMode parse(String str) {
     // regexp predicate is less efficient than like predicates.
     public static final String LIKE_PREDICATE_CONSOLIDATE_MIN = "like_predicate_consolidate_min";
 
+    public static final String DISABLE_GENERATED_COLUMN_REWRITE = "disable_generated_column_rewrite";
+
     public static final List<String> DEPRECATED_VARIABLES = ImmutableList.<String>builder()
             .add(CODEGEN_LEVEL)
             .add(MAX_EXECUTION_TIME)
@@ -1520,6 +1522,9 @@ public static MaterializedViewRewriteMode parse(String str) {
     @VarAttr(name = ENABLE_HYPERSCAN_VEC)
     private boolean enableHyperscanVec = true;
 
+    @VarAttr(name = DISABLE_GENERATED_COLUMN_REWRITE, flag = VariableMgr.INVISIBLE)
+    private boolean disableGeneratedColumnRewrite = false;
+
     public int getCboPruneJsonSubfieldDepth() {
         return cboPruneJsonSubfieldDepth;
     }
@@ -4037,6 +4042,10 @@ public void setLikePredicateConsolidateMin(int value) {
         this.likePredicateConsolidateMin = value;
     }
 
+    public boolean isDisableGeneratedColumnRewrite() {
+        return disableGeneratedColumnRewrite;
+    }
+
     // Serialize to thrift object
     // used for rest api
     public TQueryOptions toThrift() {

fe/fe-core/src/main/java/com/starrocks/sql/analyzer/QueryAnalyzer.java

@@ -132,6 +132,9 @@ public GeneratedColumnExprMappingCollector() {
         }
 
         public Void process(ParseNode node, Scope scope) {
+            if (session.getSessionVariable().isDisableGeneratedColumnRewrite()) {
+                return null;
+            }
             return node.accept(this, scope);
         }
 

fe/fe-core/src/main/java/com/starrocks/sql/optimizer/rewrite/scalar/ReplaceScalarOperatorRule.java

@@ -29,11 +29,10 @@ public ReplaceScalarOperatorRule(Map<ScalarOperator, ColumnRefOperator> translat
 
     @Override
     public ScalarOperator visit(ScalarOperator scalarOperator, ScalarOperatorRewriteContext context) {
-        for (Map.Entry<ScalarOperator, ColumnRefOperator> m : translateMap.entrySet()) {
-            if (ScalarOperator.isEquivalent(m.getKey(), scalarOperator)) {
-                return m.getValue();
-            }
+        if (translateMap.containsKey(scalarOperator)) {
+            return translateMap.get(scalarOperator);
         }
+
         return scalarOperator;
     }
 }

fe/fe-core/src/test/java/com/starrocks/sql/plan/GeneratedColumnTest.java

@@ -137,11 +137,11 @@ public void test() throws Exception {
         assertContains(plan, "OUTPUT EXPRS:5: expr");
         assertContains(plan, " group by: 1: v1, 2: v2");
 
-        sql = " select tmc.v1 + 1 from tmc as v,tmc2 as tmc";
+        sql = " select v.v1 + 1 from tmc as v,tmc2 as tmc";
         plan = getFragmentPlan(sql);
         assertContains(plan, "<slot 3> : 3: v3");
 
-        sql = " select tmc.v1 + 1 from tmc as v,tmc2 as tmc";
+        sql = " select v.v1 + 1 from tmc as v,tmc2 as tmc";
         plan = getFragmentPlan(sql);
         assertContains(plan, "<slot 3> : 3: v3");
 

test/lib/sr_sql_lib.py

@@ -2540,6 +2540,16 @@ def set_first_tablet_bad_and_recover(self, table_name):
             else:
                 break
 
+    def assert_is_identical_explain_plan(self, query1, query2):
+        """
+        assert whether two plans from query1 and query2 are identical
+        """
+        sql1 = "explain %s" % query1
+        sql2 = "explain %s" % query2
+        res1 = self.execute_sql(sql1, True)
+        res2 = self.execute_sql(sql2, True)
+        tools.assert_true(res1 == res2, "assert two plans are different, plan1: {}, plan2: {}".format(res1["result"], res2["result"]))
+
     def assert_explain_contains(self, query, *expects):
         """
         assert explain result contains expect string