diff --git a/drivers/mysql/include_private/orm/drivers/mysql/mysqlresult_p.hpp b/drivers/mysql/include_private/orm/drivers/mysql/mysqlresult_p.hpp
index 52ee620c7..8198c18d9 100644
--- a/drivers/mysql/include_private/orm/drivers/mysql/mysqlresult_p.hpp
+++ b/drivers/mysql/include_private/orm/drivers/mysql/mysqlresult_p.hpp
@@ -89,7 +89,7 @@ namespace Orm::Drivers::MySql
         QVariant getValueForPrepared(ResultFieldsSizeType index) const;
 
         /*! Throw an exception if an index for result fields vector is out of bounds. */
-        void throwIfBadResultFieldsIndex(ResultFieldsSizeType index) const;
+        void throwIfBadResultFieldsIndex(size_type index) const;
 
         /* Data members */
         /* Common for both */
diff --git a/drivers/mysql/src/orm/drivers/mysql/mysqlresult.cpp b/drivers/mysql/src/orm/drivers/mysql/mysqlresult.cpp
index 7780239cf..06ca4a3b8 100644
--- a/drivers/mysql/src/orm/drivers/mysql/mysqlresult.cpp
+++ b/drivers/mysql/src/orm/drivers/mysql/mysqlresult.cpp
@@ -419,10 +419,10 @@ QVariant MySqlResult::data(const size_type index) const
 {
     Q_D(const MySqlResult);
 
-    const auto idx = static_cast<MySqlResultPrivate::ResultFieldsSizeType>(index);
-
     // Throw an exception if an index for result fields vector is out of bounds
-    d->throwIfBadResultFieldsIndex(idx);
+    d->throwIfBadResultFieldsIndex(index);
+
+    const auto idx = static_cast<MySqlResultPrivate::ResultFieldsSizeType>(index);
 
     if (d->preparedQuery)
         return d->getValueForPrepared(idx);
@@ -434,10 +434,10 @@ bool MySqlResult::isNull(const size_type index) const
 {
     Q_D(const MySqlResult);
 
-    const auto idx = static_cast<MySqlResultPrivate::ResultFieldsSizeType>(index);
-
     // Throw an exception if an index for result fields vector is out of bounds
-    d->throwIfBadResultFieldsIndex(idx);
+    d->throwIfBadResultFieldsIndex(index);
+
+    const auto idx = static_cast<MySqlResultPrivate::ResultFieldsSizeType>(index);
 
    /* MyField::isNull is populated for prepared statements only.
       The row/result set/data must be fetched first to obtain the correct result. ❗ */
diff --git a/drivers/mysql/src/orm/drivers/mysql/mysqlresult_p.cpp b/drivers/mysql/src/orm/drivers/mysql/mysqlresult_p.cpp
index 386854f31..6b18652b4 100644
--- a/drivers/mysql/src/orm/drivers/mysql/mysqlresult_p.cpp
+++ b/drivers/mysql/src/orm/drivers/mysql/mysqlresult_p.cpp
@@ -368,12 +368,12 @@ QVariant MySqlResultPrivate::getValueForPrepared(const ResultFieldsSizeType inde
 }
 
 void
-MySqlResultPrivate::throwIfBadResultFieldsIndex(const ResultFieldsSizeType index) const
+MySqlResultPrivate::throwIfBadResultFieldsIndex(const size_type index) const
 {
     const auto fieldsCount = resultFields.size();
 
     // Nothing to do
-    if (index >= 0 || index < fieldsCount)
+    if (index >= 0 || index < static_cast<size_type>(fieldsCount))
         return;
 
     throw Exceptions::OutOfRangeError(