From 54fcfb20c517dfe48d528b9f6677273549be70b7 Mon Sep 17 00:00:00 2001
From: Andrew Hutchings <andrew@linuxjedi.co.uk>
Date: Tue, 27 Sep 2016 17:31:05 +0100
Subject: [PATCH] Fix decimal to date/datetime casting

---
 utils/dataconvert/dataconvert.cpp |  9 ++++++++-
 utils/funcexp/func_cast.cpp       | 31 ++++++++-----------------------
 2 files changed, 16 insertions(+), 24 deletions(-)

diff --git a/utils/dataconvert/dataconvert.cpp b/utils/dataconvert/dataconvert.cpp
index 327a21ba3..7f93821f7 100644
--- a/utils/dataconvert/dataconvert.cpp
+++ b/utils/dataconvert/dataconvert.cpp
@@ -1805,6 +1805,14 @@ int64_t DataConvert::intToDate(int64_t data)
 	//snprintf( buf, 10, "%llu", (long long unsigned int)data);
 	//string date = buf;
 	char buf[21] = {0};
+  	Date aday;
+    if (data == 0)
+    {
+        aday.year = 0;
+        aday.month = 0;
+    	aday.day = 0;
+        return *(reinterpret_cast<uint32_t*>(&aday));
+    }
 	snprintf( buf, 15, "%llu", (long long unsigned int)data);
 
 	string year, month, day, hour, min, sec, msec;
@@ -1866,7 +1874,6 @@ int64_t DataConvert::intToDate(int64_t data)
 		default:
 			return -1;
 	}
-	Date aday;
 	if (year.empty())
 	{
 		// MMDD format. assume current year
diff --git a/utils/funcexp/func_cast.cpp b/utils/funcexp/func_cast.cpp
index 2c032e99b..0bf45a3fc 100644
--- a/utils/funcexp/func_cast.cpp
+++ b/utils/funcexp/func_cast.cpp
@@ -510,20 +510,12 @@ int32_t Func_cast_date::getDateIntVal(rowgroup::Row& row,
 		case execplan::CalpontSystemCatalog::DECIMAL:
         case execplan::CalpontSystemCatalog::UDECIMAL:
 		{
-			if (parm[0]->data()->resultType().scale != 0)
-			{
+			val = dataconvert::DataConvert::intToDate(parm[0]->data()->getIntVal(row, isNull));
+			if (val == -1)
 				isNull = true;
-				break;
-			}
 			else
-			{
-				val = dataconvert::DataConvert::intToDate(parm[0]->data()->getIntVal(row, isNull));
-				if (val == -1)
-					isNull = true;
-				else
-					return val;
-				break;
-			}
+				return val;
+            break;
 		}
 		case execplan::CalpontSystemCatalog::VARCHAR:
 		case execplan::CalpontSystemCatalog::CHAR:
@@ -715,18 +707,11 @@ int64_t Func_cast_datetime::getDatetimeIntVal(rowgroup::Row& row,
 		case execplan::CalpontSystemCatalog::DECIMAL:
         case execplan::CalpontSystemCatalog::UDECIMAL:
 		{
-			if (parm[0]->data()->resultType().scale)
-			{
-				val = dataconvert::DataConvert::intToDatetime(parm[0]->data()->getIntVal(row, isNull));
-				if (val == -1)
-					isNull = true;
-				else
-					return val;
-			}
-			else
-			{
+			val = dataconvert::DataConvert::intToDatetime(parm[0]->data()->getIntVal(row, isNull));
+			if (val == -1)
 				isNull = true;
-			}
+			else
+				return val;
 			break;
 		}
 		case execplan::CalpontSystemCatalog::VARCHAR: