From da3cc95077609f476cb9d768f28b9fd1f591da60 Mon Sep 17 00:00:00 2001
From: Aleksei Antipovskii <aleksei.antipovskii@mariadb.com>
Date: Tue, 2 Sep 2025 02:40:52 +0200
Subject: [PATCH] Prefer to use floating point instead of decimal to match
 server behaviour.

---
 utils/dataconvert/dataconvert.cpp | 33 ++++++-------------------------
 1 file changed, 6 insertions(+), 27 deletions(-)

diff --git a/utils/dataconvert/dataconvert.cpp b/utils/dataconvert/dataconvert.cpp
index 44f671447..86e0174df 100644
--- a/utils/dataconvert/dataconvert.cpp
+++ b/utils/dataconvert/dataconvert.cpp
@@ -2949,7 +2949,7 @@ void DataConvert::joinColTypeForUnion(datatypes::SystemCatalog::TypeHolderStd& u
         case datatypes::SystemCatalog::UINT:
         case datatypes::SystemCatalog::UBIGINT:
         case datatypes::SystemCatalog::UDECIMAL:
-
+        {
           if (type.scale != 0 && (unionedType.scale != 0 || isDecimal(unionedType.colDataType)))
           {
             const unsigned int digitsBeforeDecimal = type.precision - type.scale;
@@ -3012,7 +3012,7 @@ void DataConvert::joinColTypeForUnion(datatypes::SystemCatalog::TypeHolderStd& u
           }
 
           break;
-
+        }
         case datatypes::SystemCatalog::DATE:
           unionedType.colDataType = datatypes::SystemCatalog::CHAR;
           unionedType.colWidth = 20;
@@ -3042,10 +3042,6 @@ void DataConvert::joinColTypeForUnion(datatypes::SystemCatalog::TypeHolderStd& u
         case datatypes::SystemCatalog::UFLOAT:
         case datatypes::SystemCatalog::UDOUBLE:
         case datatypes::SystemCatalog::LONGDOUBLE:
-          if (datatypes::isWideDecimalType(type.colDataType, type.colWidth))
-            unionedType = type;
-          break;
-
         default: break;
       }
 
@@ -3249,21 +3245,13 @@ void DataConvert::joinColTypeForUnion(datatypes::SystemCatalog::TypeHolderStd& u
         case datatypes::SystemCatalog::UBIGINT:
         case datatypes::SystemCatalog::UFLOAT:
         case datatypes::SystemCatalog::UDOUBLE:
+        case datatypes::SystemCatalog::DECIMAL:
+        case datatypes::SystemCatalog::UDECIMAL:
           unionedType.colDataType = datatypes::SystemCatalog::DOUBLE;
           unionedType.scale = 0;
           unionedType.colWidth = sizeof(double);
           break;
 
-        case datatypes::SystemCatalog::DECIMAL:
-        case datatypes::SystemCatalog::UDECIMAL:
-          if (unionedType.colWidth != datatypes::MAXDECIMALWIDTH)
-          {
-            unionedType.colDataType = datatypes::SystemCatalog::DOUBLE;
-            unionedType.scale = 0;
-            unionedType.colWidth = sizeof(double);
-          }
-          break;
-
         default: break;
       }
 
@@ -3313,23 +3301,14 @@ void DataConvert::joinColTypeForUnion(datatypes::SystemCatalog::TypeHolderStd& u
         case datatypes::SystemCatalog::UFLOAT:
         case datatypes::SystemCatalog::UDOUBLE:
         case datatypes::SystemCatalog::LONGDOUBLE:
+        case datatypes::SystemCatalog::DECIMAL:
+        case datatypes::SystemCatalog::UDECIMAL:
           unionedType.colDataType = datatypes::SystemCatalog::LONGDOUBLE;
           unionedType.scale = (type.scale > unionedType.scale) ? type.scale : unionedType.scale;
           unionedType.colWidth = sizeof(long double);
           unionedType.precision = -1;
           break;
 
-        case datatypes::SystemCatalog::DECIMAL:
-        case datatypes::SystemCatalog::UDECIMAL:
-          if (unionedType.colWidth != datatypes::MAXDECIMALWIDTH)
-          {
-            unionedType.colDataType = datatypes::SystemCatalog::LONGDOUBLE;
-            unionedType.scale = (type.scale > unionedType.scale) ? type.scale : unionedType.scale;
-            unionedType.colWidth = sizeof(long double);
-            unionedType.precision = -1;
-          }
-          break;
-
         default: break;
       }