From 13a3550d8ee5f46a7b9a9d85b1cb290592ff6217 Mon Sep 17 00:00:00 2001
From: xzj7019 <131111794+xzj7019@users.noreply.github.com>
Date: Sun, 24 Dec 2023 01:41:43 +0800
Subject: [PATCH] [nereids] fix join fd computing bug (#28849)

---
 .../doris/nereids/trees/plans/logical/LogicalJoin.java      | 4 ++--
 .../doris/nereids/rules/rewrite/EliminateJoinByFkTest.java  | 6 ++++--
 2 files changed, 6 insertions(+), 4 deletions(-)

diff --git a/fe/fe-core/src/main/java/org/apache/doris/nereids/trees/plans/logical/LogicalJoin.java b/fe/fe-core/src/main/java/org/apache/doris/nereids/trees/plans/logical/LogicalJoin.java
index c771f0372e..773dbce5fc 100644
--- a/fe/fe-core/src/main/java/org/apache/doris/nereids/trees/plans/logical/LogicalJoin.java
+++ b/fe/fe-core/src/main/java/org/apache/doris/nereids/trees/plans/logical/LogicalJoin.java
@@ -423,8 +423,8 @@ public class LogicalJoin<LEFT_CHILD_TYPE extends Plan, RIGHT_CHILD_TYPE extends
         // TODO: consider Null-safe hash condition when left and rigth is not nullable
         boolean isLeftUnique = left().getLogicalProperties()
                 .getFunctionalDependencies().isUnique(keys.first);
-        boolean isRightUnique = left().getLogicalProperties()
-                .getFunctionalDependencies().isUnique(keys.first);
+        boolean isRightUnique = right().getLogicalProperties()
+                .getFunctionalDependencies().isUnique(keys.second);
         Builder fdBuilder = new Builder();
         if (joinType.isInnerJoin()) {
             // inner join propagate uniforms slots
diff --git a/fe/fe-core/src/test/java/org/apache/doris/nereids/rules/rewrite/EliminateJoinByFkTest.java b/fe/fe-core/src/test/java/org/apache/doris/nereids/rules/rewrite/EliminateJoinByFkTest.java
index 1faaca4f3f..721e94b144 100644
--- a/fe/fe-core/src/test/java/org/apache/doris/nereids/rules/rewrite/EliminateJoinByFkTest.java
+++ b/fe/fe-core/src/test/java/org/apache/doris/nereids/rules/rewrite/EliminateJoinByFkTest.java
@@ -107,7 +107,8 @@ class EliminateJoinByFkTest extends TestWithFeService implements MemoPatternMatc
 
     @Test
     void testMultiJoin() throws Exception {
-        addConstraint("Alter table foreign_null add constraint uk unique (id3)\n");
+        addConstraint("Alter table foreign_null add constraint uk_id3 unique (id3)\n");
+        addConstraint("Alter table foreign_not_null add constraint uk_id2 unique (id2)\n");
         String sql = "select id1 from "
                 + "foreign_null inner join foreign_not_null on id2 = id3\n"
                 + "inner join pri on id1 = id3";
@@ -116,6 +117,7 @@ class EliminateJoinByFkTest extends TestWithFeService implements MemoPatternMatc
                 .rewrite()
                 .nonMatch(logicalOlapScan().when(scan -> scan.getTable().getName().equals("pri")))
                 .printlnTree();
-        dropConstraint("Alter table foreign_null drop constraint uk\n");
+        dropConstraint("Alter table foreign_null drop constraint uk_id3\n");
+        dropConstraint("Alter table foreign_not_null drop constraint uk_id2");
     }
 }