diff --git a/src/DbConfig.php b/src/DbConfig.php
index cbc218f..fb28469 100644
--- a/src/DbConfig.php
+++ b/src/DbConfig.php
@@ -24,13 +24,29 @@ class DbConfig implements IConfig {
     /** @var array<string, DbConfigValueInfo> */
     private array $values = [];
 
+    /** @var string[] */
+    private array $extraFieldNames;
+
+    /** @var mixed[] */
+    private array $extraFieldValues;
+
+    /**
+     * @param IDbConnection $dbConn
+     * @param string $tableName
+     * @param string $nameField
+     * @param string $valueField
+     * @param array<string, mixed> $extraFields
+     */
     public function __construct(
         IDbConnection $dbConn,
         private string $tableName,
         private string $nameField = 'config_name',
-        private string $valueField = 'config_value'
+        private string $valueField = 'config_value',
+        array $extraFields = [],
     ) {
         $this->cache = new DbStatementCache($dbConn);
+        $this->extraFieldNames = array_keys($extraFields);
+        $this->extraFieldValues = array_values($extraFields);
     }
 
     public static function validateName(string $name): bool {
@@ -90,15 +106,23 @@ class DbConfig implements IConfig {
             $names = array_values($names);
             $nameCount = count($names);
 
-            $stmt = $this->cache->get(sprintf(
+            $query = sprintf(
                 'SELECT COUNT(*) FROM %s WHERE %s IN (%s)',
                 $this->tableName, $this->nameField,
                 DbTools::prepareListString($nameCount)
-            ));
-            for($i = 0; $i < $nameCount; ++$i)
-                $stmt->addParameter($i + 1, $names[$i]);
-            $stmt->execute();
+            );
+            foreach($this->extraFieldNames as $extraFieldName)
+                $query .= sprintf(' AND %s = ?', $extraFieldName);
 
+            $stmt = $this->cache->get($query);
+
+            $args = 0;
+            foreach($names as $name)
+                $stmt->addParameter(++$args, $name);
+            foreach($this->extraFieldValues as $extraFieldValue)
+                $stmt->addParameter(++$args, $extraFieldValue);
+
+            $stmt->execute();
             $result = $stmt->getResult();
             if($result->next())
                 return $result->getInteger(0) >= $nameCount;
@@ -117,14 +141,21 @@ class DbConfig implements IConfig {
             unset($this->values[$name]);
 
         $nameCount = count($names);
-        $stmt = $this->cache->get(sprintf(
+        $query = sprintf(
             'DELETE FROM %s WHERE %s IN (%s)',
             $this->tableName, $this->nameField,
             DbTools::prepareListString($nameCount)
-        ));
+        );
+        foreach($this->extraFieldNames as $extraFieldName)
+            $query .= sprintf(' AND %s = ?', $extraFieldName);
 
-        for($i = 0; $i < $nameCount; ++$i)
-            $stmt->addParameter($i + 1, $names[$i]);
+        $stmt = $this->cache->get($query);
+
+        $args = 0;
+        foreach($names as $name)
+            $stmt->addParameter(++$args, $name);
+        foreach($this->extraFieldValues as $extraFieldValue)
+            $stmt->addParameter(++$args, $extraFieldValue);
 
         $stmt->execute();
     }
@@ -136,6 +167,8 @@ class DbConfig implements IConfig {
         $hasRange = $range !== 0;
 
         $query = sprintf('SELECT %s, %s FROM %s', $this->nameField, $this->valueField, $this->tableName);
+        foreach($this->extraFieldNames as $i => $extraFieldName)
+            $query .= sprintf(' %s %s = ?', $i < 1 ? 'WHERE' : 'AND', $extraFieldName);
         if($hasRange) {
             if($range < 0)
                 throw new InvalidArgumentException('$range must be a positive integer.');
@@ -146,10 +179,15 @@ class DbConfig implements IConfig {
         }
 
         $stmt = $this->cache->get($query);
+
+        $args = 0;
+        foreach($this->extraFieldValues as $extraFieldValue)
+            $stmt->addParameter(++$args, $extraFieldValue);
         if($hasRange) {
-            $stmt->addParameter(1, $range);
-            $stmt->addParameter(2, $offset);
+            $stmt->addParameter(++$args, $range);
+            $stmt->addParameter(++$args, $offset);
         }
+
         $stmt->execute();
 
         $result = $stmt->getResult();
@@ -184,13 +222,22 @@ class DbConfig implements IConfig {
             $names = array_values($names);
             $nameCount = count($names);
 
-            $stmt = $this->cache->get(sprintf(
-                'SELECT %s, %s FROM %s WHERE config_name IN (%s)',
-                $this->nameField, $this->valueField, $this->tableName,
+            $query = sprintf(
+                'SELECT %s, %s FROM %s WHERE %s IN (%s)',
+                $this->nameField, $this->valueField, $this->tableName, $this->nameField,
                 DbTools::prepareListString($nameCount)
-            ));
-            for($i = 0; $i < $nameCount; ++$i)
-                $stmt->addParameter($i + 1, $names[$i]);
+            );
+            foreach($this->extraFieldNames as $extraFieldName)
+                $query .= sprintf(' AND %s = ?', $extraFieldName);
+
+            $stmt = $this->cache->get($query);
+
+            $args = 0;
+            foreach($names as $name)
+                $stmt->addParameter(++$args, $name);
+            foreach($this->extraFieldValues as $extraFieldValue)
+                $stmt->addParameter(++$args, $extraFieldValue);
+
             $stmt->execute();
 
             $result = $stmt->getResult();
@@ -207,9 +254,16 @@ class DbConfig implements IConfig {
         if(empty($values))
             return;
 
+        $fields = [$this->nameField, $this->valueField];
+        if(count($this->extraFieldNames) > 0)
+            $fields = array_merge($fields, $this->extraFieldNames);
+        $fieldCount = count($fields);
+        $fields = implode(', ', $fields);
+
         $stmt = $this->cache->get(sprintf(
-            'INSERT INTO %s (%s, %s) VALUES (?, ?)',
-            $this->tableName, $this->nameField, $this->valueField
+            'INSERT INTO %s (%s) VALUES (%s)',
+            $this->tableName, $fields,
+            DbTools::prepareListString($fieldCount)
         ));
 
         foreach($values as $name => $value) {
@@ -225,8 +279,12 @@ class DbConfig implements IConfig {
 
             $this->removeValues($name);
 
-            $stmt->addParameter(1, $name);
-            $stmt->addParameter(2, serialize($value));
+            $args = 0;
+            $stmt->addParameter(++$args, $name);
+            $stmt->addParameter(++$args, serialize($value));
+            foreach($this->extraFieldValues as $extraFieldValue)
+                $stmt->addParameter(++$args, $extraFieldValue);
+
             $stmt->execute();
         }
     }
diff --git a/tests/DbConfigTest.php b/tests/DbConfigTest.php
index 8406126..a6338c8 100644
--- a/tests/DbConfigTest.php
+++ b/tests/DbConfigTest.php
@@ -15,6 +15,7 @@ use PHPUnit\Framework\TestCase;
  * @covers \Syokuhou\GetValuesTrait
  */
 final class DbConfigTest extends TestCase {
+    private \Index\Data\IDbConnection $dbConn;
     private \Syokuhou\DbConfig $config;
 
     private const VALUES = [
@@ -34,18 +35,33 @@ final class DbConfigTest extends TestCase {
         'test.int' => 'i:243230;',
     ];
 
-    protected function setUp(): void {
-        $dbConn = \Index\Data\DbTools::create('sqlite::memory:');
-        $dbConn->execute('CREATE TABLE skh_config (config_name TEXT NOT NULL COLLATE NOCASE, config_value BLOB NOT NULL, PRIMARY KEY (config_name))');
+    private const USER_VALUES = [
+        'mobile.left_handed' => ['b:0;', 'b:1;'],
+        'profile.allow_indexing' => ['b:1;', 'b:0;'],
+    ];
 
-        $stmt = $dbConn->prepare('INSERT INTO skh_config (config_name, config_value) VALUES (?, ?)');
+    protected function setUp(): void {
+        $this->dbConn = \Index\Data\DbTools::create('sqlite::memory:');
+        $this->dbConn->execute('CREATE TABLE skh_config (config_name TEXT NOT NULL COLLATE NOCASE, config_value BLOB NOT NULL, PRIMARY KEY (config_name))');
+        $this->dbConn->execute('CREATE TABLE skh_user_settings (user_id INTEGER NOT NULL, setting_name TEXT NOT NULL COLLATE NOCASE, setting_value BLOB NOT NULL, PRIMARY KEY (user_id, setting_name))');
+
+        $stmt = $this->dbConn->prepare('INSERT INTO skh_config (config_name, config_value) VALUES (?, ?)');
         foreach(self::VALUES as $name => $value) {
             $stmt->addParameter(1, $name);
             $stmt->addParameter(2, $value);
             $stmt->execute();
         }
 
-        $this->config = new \Syokuhou\DbConfig($dbConn, 'skh_config');
+        $stmt = $this->dbConn->prepare('INSERT INTO skh_user_settings (user_id, setting_name, setting_value) VALUES (?, ?, ?)');
+        for($i = 1; $i <= 10; ++$i)
+            foreach(self::USER_VALUES as $name => $value) {
+                $stmt->addParameter(1, $i);
+                $stmt->addParameter(2, $name);
+                $stmt->addParameter(3, $value[$i % 2]);
+                $stmt->execute();
+            }
+
+        $this->config = new \Syokuhou\DbConfig($this->dbConn, 'skh_config');
     }
 
     public function testScoping(): void {
@@ -152,4 +168,13 @@ final class DbConfigTest extends TestCase {
         $this->assertFalse(\Syokuhou\DbConfig::validateName('this..is.not.valid'));
         $this->assertFalse(\Syokuhou\DbConfig::validateName('First.may.Not.be.uppercase'));
     }
+
+    public function testUserSettings(): void {
+        for($i = 1; $i <= 10; ++$i) {
+            $config = new \Syokuhou\DbConfig($this->dbConn, 'skh_user_settings', 'setting_name', 'setting_value', ['user_id' => $i]);
+
+            foreach(self::USER_VALUES as $name => $value)
+                $this->assertEquals(unserialize($value[$i % 2]), $config->getBoolean($name));
+        }
+    }
 }