diff --git a/Tests/Mysqli/MysqliPreparedStatementTest.php b/Tests/Mysqli/MysqliPreparedStatementTest.php
index 3921b3dc..34fe60a7 100644
--- a/Tests/Mysqli/MysqliPreparedStatementTest.php
+++ b/Tests/Mysqli/MysqliPreparedStatementTest.php
@@ -116,8 +116,8 @@ public function testPrepareParameterKeyMappingWithSingleKey()
 
         $this->assertEquals(
             [
-                ':search' => 0,
-                ':search2' => 1,
+                ':search' => [0],
+                ':search2' => [1],
             ],
             $parameterKeyMapping
         );
diff --git a/Tests/Sqlsrv/SqlsrvPreparedStatementTest.php b/Tests/Sqlsrv/SqlsrvPreparedStatementTest.php
index 6afd8706..8625fdf7 100644
--- a/Tests/Sqlsrv/SqlsrvPreparedStatementTest.php
+++ b/Tests/Sqlsrv/SqlsrvPreparedStatementTest.php
@@ -118,8 +118,8 @@ public function testPrepareParameterKeyMappingWithSingleKey()
 
         $this->assertEquals(
             [
-                ':search' => 0,
-                ':search2' => 1,
+                ':search' => [0],
+                ':search2' => [1],
             ],
             $parameterKeyMapping
         );
diff --git a/src/Mysqli/MysqliStatement.php b/src/Mysqli/MysqliStatement.php
index f689c0b4..afda7b72 100644
--- a/src/Mysqli/MysqliStatement.php
+++ b/src/Mysqli/MysqliStatement.php
@@ -158,7 +158,7 @@ public function prepareParameterKeyMapping($sql)
         $quoteChar  = '';
         $literal    = '';
         $mapping    = [];
-        $replace    = [];
+        $position   = 0;
         $matches    = [];
         $pattern    = '/([:][a-zA-Z0-9_]+)/';
 
@@ -197,16 +197,15 @@ public function prepareParameterKeyMapping($sql)
                         $literal .= substr($substring, 0, $match[1]);
                     }
 
-                    if (isset($mapping[$match[0]])) {
-                        $mapping[$match[0]] = is_array($mapping[$match[0]]) ? $mapping[$match[0]] : [$mapping[$match[0]]];
-                        $mapping[$match[0]][] = \count($mapping);
-                    } else {
-                        $mapping[$match[0]] = \count($mapping);
+                    if (!isset($mapping[$match[0]])) {
+                        $mapping[$match[0]] = [];
                     }
-                    $endOfPlaceholder = $match[1] + strlen($match[0]);
+
+                    $mapping[$match[0]][]   = $position++;
+                    $endOfPlaceholder       = $match[1] + strlen($match[0]);
                     $beginOfNextPlaceholder = $matches[0][$i + 1][1] ?? strlen($substring);
                     $beginOfNextPlaceholder -= $endOfPlaceholder;
-                    $literal .= '?' . substr($substring, $endOfPlaceholder, $beginOfNextPlaceholder);
+                    $literal                .= '?' . substr($substring, $endOfPlaceholder, $beginOfNextPlaceholder);
                 }
             } else {
                 $literal .= $substring;
@@ -378,14 +377,9 @@ public function execute(?array $parameters = null)
                 foreach ($this->bindedValues as $key => &$value) {
                     $paramKey = $this->parameterKeyMapping[$key];
 
-                    if (is_scalar($this->parameterKeyMapping[$key])) {
-                        $params[$paramKey] =& $value;
-                        $types[$paramKey]  = $this->typesKeyMapping[$key];
-                    } else {
-                        foreach ($paramKey as $currentKey) {
-                            $params[$currentKey] =& $value;
-                            $types[$currentKey]  = $this->typesKeyMapping[$key];
-                        }
+                    foreach ($paramKey as $currentKey) {
+                        $params[$currentKey] =& $value;
+                        $types[$currentKey]  = $this->typesKeyMapping[$key];
                     }
                 }
             } else {
diff --git a/src/Sqlsrv/SqlsrvStatement.php b/src/Sqlsrv/SqlsrvStatement.php
index 9bff16df..e93599fe 100644
--- a/src/Sqlsrv/SqlsrvStatement.php
+++ b/src/Sqlsrv/SqlsrvStatement.php
@@ -163,7 +163,7 @@ public function prepareParameterKeyMapping($sql)
         $quoteChar  = '';
         $literal    = '';
         $mapping    = [];
-        $replace    = [];
+        $position   = 0;
         $matches    = [];
         $pattern    = '/([:][a-zA-Z0-9_]+)/';
 
@@ -202,17 +202,15 @@ public function prepareParameterKeyMapping($sql)
                         $literal .= substr($substring, 0, $match[1]);
                     }
 
-                    if (isset($mapping[$match[0]])) {
-                        $mapping[$match[0]] = is_array($mapping[$match[0]]) ? $mapping[$match[0]] : [$mapping[$match[0]]];
-                        $mapping[$match[0]][] = \count($mapping);
-                    } else {
-                        $mapping[$match[0]] = \count($mapping);
+                    if (!isset($mapping[$match[0]])) {
+                        $mapping[$match[0]] = [];
                     }
 
+                    $mapping[$match[0]][]   = $position++;
                     $endOfPlaceholder       = $match[1] + strlen($match[0]);
                     $beginOfNextPlaceholder = $matches[0][$i + 1][1] ?? strlen($substring);
                     $beginOfNextPlaceholder -= $endOfPlaceholder;
-                    $literal .= '?' . substr($substring, $endOfPlaceholder, $beginOfNextPlaceholder);
+                    $literal                .= '?' . substr($substring, $endOfPlaceholder, $beginOfNextPlaceholder);
                 }
             } else {
                 $literal .= $substring;
@@ -492,12 +490,8 @@ private function prepare()
             if (isset($this->parameterKeyMapping[$key])) {
                 $paramKey = $this->parameterKeyMapping[$key];
 
-                if (is_scalar($this->parameterKeyMapping[$key])) {
-                    $params[$paramKey] = $variable;
-                } else {
-                    foreach ($paramKey as $currentKey) {
-                        $params[$currentKey] = $variable;
-                    }
+                foreach ($paramKey as $currentKey) {
+                    $params[$currentKey] = $variable;
                 }
             } else {
                 $params[] = $variable;