From c69474b03af466ef0e5e93dd1ebd69686c6d2016 Mon Sep 17 00:00:00 2001
From: ganyang <ganyang2@huawei.com>
Date: Thu, 11 Aug 2022 14:41:13 +0800
Subject: [PATCH] add computeHashHook

---
 src/gausskernel/storage/access/hash/hashfunc.cpp | 3 +++
 src/include/access/hash.h                        | 2 ++
 src/include/knl/knl_session.h                    | 1 +
 3 files changed, 6 insertions(+)

diff --git a/src/gausskernel/storage/access/hash/hashfunc.cpp b/src/gausskernel/storage/access/hash/hashfunc.cpp
index 847f65404..f48a77ea7 100644
--- a/src/gausskernel/storage/access/hash/hashfunc.cpp
+++ b/src/gausskernel/storage/access/hash/hashfunc.cpp
@@ -708,6 +708,9 @@ Datum compute_hash(Oid type, Datum value, char locator)
             return DirectFunctionCall1(uuid_hash, value);
 
         default:
+            if (u_sess->hook_cxt.computeHashHook != NULL) {
+                return ((computeHashFunc)(u_sess->hook_cxt.computeHashHook))(type, value, locator);
+            }
             ereport(ERROR, (errcode(ERRCODE_WRONG_OBJECT_TYPE),
                             errmsg("Unhandled datatype for modulo or hash distribution\n")));
     }
diff --git a/src/include/access/hash.h b/src/include/access/hash.h
index 081622558..56b0dcdec 100644
--- a/src/include/access/hash.h
+++ b/src/include/access/hash.h
@@ -440,4 +440,6 @@ extern uint32 hash_multikey(MultiHashKey* mkeys);
 
 #define GetBucketID(hashval, hashmapsize)  (compute_modulo(abs((int)hashval), hashmapsize))
 
+typedef Datum (*computeHashFunc)(Oid type, Datum value, char locator);
+
 #endif   /* HASH_H */
diff --git a/src/include/knl/knl_session.h b/src/include/knl/knl_session.h
index 8363217f0..cde82ff7a 100644
--- a/src/include/knl/knl_session.h
+++ b/src/include/knl/knl_session.h
@@ -2640,6 +2640,7 @@ typedef struct knl_u_hook_context {
     void *analyzerRoutineHook;
     void *transformStmtHook;
     void *execInitExprHook;
+    void *computeHashHook;
 } knl_u_hook_context;
 
 typedef struct knl_session_context {