From 9c48ac79c81b99f9a2c2107dffef02f59d80831f Mon Sep 17 00:00:00 2001
From: Robert Schulze <robert@clickhouse.com>
Date: Sun, 22 Jan 2023 16:16:56 +0000
Subject: [PATCH] Fix issue #45195

---
 src/Compression/CompressionCodecGorilla.cpp   |  2 +-
 .../02536_delta_gorilla_corruption.reference  |  9 +++++
 .../02536_delta_gorilla_corruption.sql        | 34 +++++++++++++++++++
 3 files changed, 44 insertions(+), 1 deletion(-)
 create mode 100644 tests/queries/0_stateless/02536_delta_gorilla_corruption.reference
 create mode 100644 tests/queries/0_stateless/02536_delta_gorilla_corruption.sql

diff --git a/src/Compression/CompressionCodecGorilla.cpp b/src/Compression/CompressionCodecGorilla.cpp
index cbae30d774e..6c7c7138776 100644
--- a/src/Compression/CompressionCodecGorilla.cpp
+++ b/src/Compression/CompressionCodecGorilla.cpp
@@ -403,7 +403,7 @@ UInt32 CompressionCodecGorilla::doCompressData(const char * source, UInt32 sourc
         break;
     }
 
-    return 1 + 1 + result_size;
+    return 2 + bytes_to_skip + result_size;
 }
 
 void CompressionCodecGorilla::doDecompressData(const char * source, UInt32 source_size, char * dest, UInt32 uncompressed_size) const
diff --git a/tests/queries/0_stateless/02536_delta_gorilla_corruption.reference b/tests/queries/0_stateless/02536_delta_gorilla_corruption.reference
new file mode 100644
index 00000000000..82220c1598a
--- /dev/null
+++ b/tests/queries/0_stateless/02536_delta_gorilla_corruption.reference
@@ -0,0 +1,9 @@
+Original bug: the same query executed multiple times yielded different results.
+For unclear reasons this happened only in Release builds, not in Debug builds.
+0
+0
+0
+The same issue in a much smaller repro happens also in Debug builds
+0
+1
+3
diff --git a/tests/queries/0_stateless/02536_delta_gorilla_corruption.sql b/tests/queries/0_stateless/02536_delta_gorilla_corruption.sql
new file mode 100644
index 00000000000..94ee6c03c5c
--- /dev/null
+++ b/tests/queries/0_stateless/02536_delta_gorilla_corruption.sql
@@ -0,0 +1,34 @@
+select 'Original bug: the same query executed multiple times yielded different results.';
+select 'For unclear reasons this happened only in Release builds, not in Debug builds.';
+
+drop table if exists bug_delta_gorilla;
+
+create table bug_delta_gorilla
+(value_bug UInt64 codec (Delta, Gorilla))
+engine = MergeTree
+order by tuple()
+as (select 0 from numbers(30000000));
+
+select count(*)
+from bug_delta_gorilla
+where 0 <> value_bug;
+
+select count(*)
+from bug_delta_gorilla
+where 0 <> value_bug;
+
+select count(*)
+from bug_delta_gorilla
+where 0 <> value_bug;
+
+drop table if exists bug_delta_gorilla;
+
+select 'The same issue in a much smaller repro happens also in Debug builds';
+
+create table bug_delta_gorilla (val UInt64 codec (Delta, Gorilla))
+engine = MergeTree
+order by val;
+insert into bug_delta_gorilla values (0)(1)(3);
+select * from bug_delta_gorilla;
+
+drop table if exists bug_delta_gorilla;