From adb46fa17498e02b1f92c71735f5ab175d4ff4bf Mon Sep 17 00:00:00 2001
From: yariks5s <yaroslav.briukhovetskyi@clickhouse.com>
Date: Wed, 26 Jul 2023 15:20:54 +0000
Subject: [PATCH] Revert "Implemented requested changes"

This reverts commit db4735a10508e02b50565bba8a1e71161df90f82.
---
 src/Functions/array/arrayIntersect.cpp | 47 +++++++++++++++-----------
 1 file changed, 27 insertions(+), 20 deletions(-)

diff --git a/src/Functions/array/arrayIntersect.cpp b/src/Functions/array/arrayIntersect.cpp
index 83b26b56071..7a8bde7ab5f 100644
--- a/src/Functions/array/arrayIntersect.cpp
+++ b/src/Functions/array/arrayIntersect.cpp
@@ -510,7 +510,7 @@ ColumnPtr FunctionArrayIntersect::execute(const UnpackedArrays & arrays, Mutable
         map.clear();
 
         bool all_has_nullable = all_nullable;
-        bool current_has_nullable;
+        bool current_has_nullable = false;
 
         for (size_t arg_num = 0; arg_num < args; ++arg_num)
         {
@@ -549,8 +549,7 @@ ColumnPtr FunctionArrayIntersect::execute(const UnpackedArrays & arrays, Mutable
                         ++(*value);
                 }
             }
-            // We update offsets for all the arrays except the first one. Offsets for the first array would be updated later. 
-            // It is needed to iterate the first array again so that the elements in the result would have fixed order.
+
             if (arg_num)
             {
                 prev_off[arg_num] = off;
@@ -571,21 +570,15 @@ ColumnPtr FunctionArrayIntersect::execute(const UnpackedArrays & arrays, Mutable
         else
             off = (*arg.offsets)[row];
 
-        bool is_map_serialized = false;
         for (auto i : collections::range(prev_off[0], off))
         {
+            all_has_nullable = all_nullable;
+            current_has_nullable = false;
             typename Map::LookupResult pair = nullptr;
 
             if (arg.null_map && (*arg.null_map)[i])
             {
                 current_has_nullable = true;
-                if (all_has_nullable && !null_added)
-                {
-                    ++result_offset;
-                    result_data.insertDefault();
-                    null_map.push_back(1);
-                    null_added = true;
-                }
                 if (null_added)
                     continue;
             }
@@ -598,37 +591,51 @@ ColumnPtr FunctionArrayIntersect::execute(const UnpackedArrays & arrays, Mutable
             else
             {
                 const char * data = nullptr;
-                if (!is_map_serialized)
-                {
-                    pair = map.find(columns[0]->serializeValueIntoArena(i, arena, data));
-                    is_map_serialized = true;
-                }
+                pair = map.find(columns[0]->serializeValueIntoArena(i, arena, data));
             }
             prev_off[0] = off;
             if (arg.is_const)
                 prev_off[0] = 0;
 
+            if (!current_has_nullable)
+                all_has_nullable = false;
+
             if (pair && pair->getMapped() == args)
             {
-                // We increase pair->getMapped() here to not skip duplicate values from the first array.
                 ++pair->getMapped();
                 ++result_offset;
                 if constexpr (is_numeric_column)
                 {
-                    result_data.insertValue(pair->getKey());
+                    if (pair->getKey() == columns[0]->getElement(i))
+                    {
+                        result_data.insertValue(pair->getKey());
+                    }
                 }
                 else if constexpr (std::is_same_v<ColumnType, ColumnString> || std::is_same_v<ColumnType, ColumnFixedString>)
                 {
-                    result_data.insertData(pair->getKey().data, pair->getKey().size);
+                    if (pair->getKey() == columns[0]->getDataAt(i))
+                    {
+                        result_data.insertData(pair->getKey().data, pair->getKey().size);
+                    }
                 }
                 else
                 {
                     const char * data = nullptr;
-                    result_data.deserializeAndInsertFromArena(pair->getKey().data);
+                    if (pair->getKey() == columns[0]->serializeValueIntoArena(i, arena, data))
+                    {
+                        result_data.deserializeAndInsertFromArena(pair->getKey().data);
+                    }
                 }
                 if (all_nullable)
                     null_map.push_back(0);
             }
+            if (all_has_nullable && !null_added)
+            {
+                ++result_offset;
+                result_data.insertDefault();
+                null_map.push_back(1);
+                null_added = true;
+            }
         }
         result_offsets.getElement(row) = result_offset;