From a9b395718262c7d02066ce245d2ea02d356bffbb Mon Sep 17 00:00:00 2001
From: Roman Nozdrin <roman.nozdrin@mariadb.com>
Date: Fri, 29 Jan 2021 15:29:39 +0000
Subject: [PATCH] MCOL-4519 RefColumn now uses the correct empty value
 iterating over the block values

---
 writeengine/wrapper/we_colop.cpp    | 5 ++++-
 writeengine/wrapper/writeengine.cpp | 4 +---
 2 files changed, 5 insertions(+), 4 deletions(-)

diff --git a/writeengine/wrapper/we_colop.cpp b/writeengine/wrapper/we_colop.cpp
index c4ca4944c..9ddb0d795 100644
--- a/writeengine/wrapper/we_colop.cpp
+++ b/writeengine/wrapper/we_colop.cpp
@@ -707,10 +707,13 @@ int ColumnOp::fillColumn(const TxnID& txnid, Column& column, Column& refCol, voi
     config.initConfigCache();
     std::vector<uint16_t> rootList;
     config.getRootIdList( rootList );
-    const uint8_t* emptyVal = getEmptyRowValue(column.colDataType, 
+    const uint8_t* emptyVal = getEmptyRowValue(column.colDataType,
                                                column.colWidth);
+    // Set TypeHandler to get empty value ptr for the ref column
+    findTypeHandler(refCol.colWidth, refCol.colDataType);
     const uint8_t* refEmptyVal = getEmptyRowValue(refCol.colDataType,
                                                   refCol.colWidth);
+    findTypeHandler(column.colWidth, column.colDataType);
     //find the dbroots which have rows for refrence column
     unsigned int i = 0, k = 0;
 
diff --git a/writeengine/wrapper/writeengine.cpp b/writeengine/wrapper/writeengine.cpp
index 96fb3a895..a350fc331 100644
--- a/writeengine/wrapper/writeengine.cpp
+++ b/writeengine/wrapper/writeengine.cpp
@@ -711,11 +711,9 @@ int WriteEngineWrapper::fillColumn(const TxnID& txnid, const OID& dataOid,
     Convertor::convertColType(refColDataType, refColWidth, refColType, isToken);
     refColOp->setColParam(refCol, 0, refColOp->getCorrectRowWidth(refColDataType, refColWidth),
                           refColDataType, refColType, (FID)refColOID, refCompressionType, dbRoot);
-    refColOp->findTypeHandler(refColOp->getCorrectRowWidth(refColDataType,
-                                                           refColWidth),
-                              refColDataType);
     colOpNewCol->setColParam(newCol, 0, newDataWidth,
                              colType.colDataType, newColType, (FID)dataOid, compressionType, dbRoot);
+    // refColOp and colOpNewCol are the same ptr.
     colOpNewCol->findTypeHandler(newDataWidth, colType.colDataType);