diff --git a/models/Test.php b/models/Test.php
new file mode 100644
index 0000000..b1c0963
--- /dev/null
+++ b/models/Test.php
@@ -0,0 +1,65 @@
+<?php
+/*
+	TPsoft.org 2000-2025
+	file for controlers/*.php
+
+	Molestones:
+	2025-05-27 21:36  Created
+*/
+
+class Test extends \TPsoft\DBmodel\DBmodel {
+
+	public $tables = array(
+		'test' => array(
+			'name'             => 'test',
+			'primary_key_name' => 'id',
+			'allow_attributes' => array(
+				'name' => 'varchar(255)',
+				'created' => 'datetime'
+			)
+		),
+	);
+
+	public function exist($primary_key = null) {
+		return $this->existRecord('test', $primary_key);
+	}
+
+	public function test($primary_key = null, $data = array()) {
+		return $this->record('test', $primary_key, $data);
+	}
+
+	public function testBy($colname, $colvalue) {
+		return $this->recordBy('test', $colname, $colvalue);
+	}
+
+	public function testSave($data = array()) {
+		return $this->test($this->exist($data) ? $data : null, $data);
+	}
+
+	public function testEmpty() {
+		return $this->recordEmpty('test');
+	}
+
+	public function testAttributes() {
+		return $this->typesAttributes('test');
+	}
+
+	public function testCount() {
+		return $this->count('test');
+	}
+
+	public function getList($search = array(), $reverse = false, $concat_or = false) {
+		return $this->search('test')
+			->where($search, $concat_or)
+			->order(array('id' => $reverse ? 'DESC' : 'ASC'))
+			->toArray();
+	}
+
+	public function testCombo($col_key, $col_value, $add_empty = false) {
+		return $this->search('test')
+			->toCombo($col_key, $col_value, $add_empty);
+	}
+
+}
+
+?>
diff --git a/src/DBmodel.php b/src/DBmodel.php
index 850c3ff..3e60935 100644
--- a/src/DBmodel.php
+++ b/src/DBmodel.php
@@ -27,7 +27,7 @@ class DBmodel
 	public $log = null;
 	public $tables = array();
 
-	public function __construct(string $dsn = null, ?string $username = null, #[\SensitiveParameter] ?string $password = null, ?array $options = null)
+	public function __construct(?string $dsn = null, ?string $username = null, #[\SensitiveParameter] ?string $password = null, ?array $options = null)
 	{
 		if (is_null($dsn)) {
 			if (DBmodel::$instance) {
diff --git a/src/Maintenance.php b/src/Maintenance.php
index 423be69..c91bada 100644
--- a/src/Maintenance.php
+++ b/src/Maintenance.php
@@ -26,17 +26,26 @@ class Maintenance
 
 	private DBmodel $dbh;
 
-	public function __construct(DBmodel $dbh)
+	public function __construct(?DBmodel $dbh)
 	{
-		$this->dbh = $dbh;
+		if (is_null($dbh)) {
+			if (!is_null(DBmodel::$instance)) {
+				$this->dbh = DBmodel::$instance;
+			} else {
+				throw new \Exception('DB handler is null');
+			}
+		} else {
+			$this->dbh = $dbh;
+		}
 	}
 
 	public function testDB($test, $test_out)
 	{
-		global $core;
 		if (is_array($test_out)) {
-			$row = $core->dbh->getRow($test);
+			$test_out = array_change_key_case($test_out, CASE_LOWER);
+			$row = $this->dbh->getRow($test);
 			if (!is_array($row)) return false;
+			$row = array_change_key_case($row, CASE_LOWER);
 			foreach ($test_out as $col => $val) {
 				if (strlen($row[$col]) != strlen($val)) {
 					$max_len = min(strlen($row[$col]), strlen($val));
@@ -51,17 +60,16 @@ class Maintenance
 			}
 			return true;
 		} else {
-			return $core->dbh->getOne($test) == $test_out;
+			return $this->dbh->getOne($test) == $test_out;
 		}
 	}
 
 	public function checkDB($test, $test_out, $fix)
 	{
-		global $core;
 		if ($this->testDB($test, $test_out)) {
 			return Maintenance::OK;
 		} else {
-			$core->dbh->query($fix);
+			$this->dbh->query($fix);
 			if ($this->testDB($test, $test_out)) {
 				return Maintenance::FIXED;
 			} else {
@@ -71,12 +79,10 @@ class Maintenance
 		return 0;
 	}
 
-	public function checkDBTable($table_index, $definition)
+	public function checkDBTable($table_name, $definition)
 	{
-		global $core;
-		$table_name = $core->tables[$table_index];
 		if (strlen($table_name) <= 0) {
-			$this->lastMessage = 'Table ' . strtoupper($table_index) . ' - invalid index';
+			$this->lastMessage = 'Table ' . strtoupper($table_name) . ' - invalid index';
 			return Maintenance::ABNORMAL;
 		}
 		$status = $this->checkDB(
@@ -87,118 +93,127 @@ class Maintenance
 			// FIX query
 			'CREATE TABLE `' . $table_name . '` (' . $definition . ')'
 		);
-		$this->lastMessage = 'Table ' . strtoupper($table_index) . ' (' . $table_name . ')';
+		$this->lastMessage = 'Table ' . strtoupper($table_name) . ' (' . $table_name . ')';
 		return $status;
 	}
 
-	public function checkDBAdd($table_index, $column, $definition)
+	public function existsColumn($table_name, $column)
+	{
+		return $this->testDB(
+			'DESCRIBE `' . $table_name . '` `' . $column . '`',
+			$column
+		);
+	}
+
+	public function checkDBAdd($table_name, $column, $definition)
 	{
-		global $core;
 		$status = $this->checkDB(
 			// TEST query
-			'DESCRIBE `' . $core->tables[$table_index] . '` `' . $column . '`',
+			'DESCRIBE `' . $table_name . '` `' . $column . '`',
 			// TEST output
 			$column,
 			// FIX query
-			'ALTER TABLE `' . $core->tables[$table_index] . '` ADD `' . $column . '` ' . $definition
+			'ALTER TABLE `' . $table_name . '` ADD `' . $column . '` ' . $definition
 		);
-		$this->lastMessage = "Added column $column to table $table_index";
+		$this->lastMessage = "Added column $column to table $table_name";
 		return $status;
 	}
 
-	public function checkDBRename($table_index, $column_old, $column_new, $definition, $test = null)
+	public function checkDBRename($table_name, $column_old, $column_new, $definition, $test = null)
 	{
-		global $core;
+		if (!$this->existsColumn($table_name, $column_old)) {
+			return Maintenance::ABNORMAL;
+		}
 		$status = $this->checkDB(
 			// TEST query
-			'DESCRIBE `' . $core->tables[$table_index] . '` `' . $column_old . '`',
+			'DESCRIBE `' . $table_name . '` `' . $column_old . '`',
 			// TEST output
 			$test,
 			// FIX query
-			'ALTER TABLE `' . $core->tables[$table_index] . '` CHANGE `' . $column_old . '` `' . $column_new . '` ' . $definition
+			'ALTER TABLE `' . $table_name . '` CHANGE `' . $column_old . '` `' . $column_new . '` ' . $definition
 		);
-		$this->lastMessage = "Renamed  column $column_old to $column_new for $table_index";
+		$this->lastMessage = "Renamed  column $column_old to $column_new for $table_name";
 		return $status;
 	}
 
-	public function checkDBRetype($table_index, $column, $new_type, $definition)
+	public function checkDBRetype($table_name, $column, $new_type, $definition)
 	{
-		global $core;
+		if (!$this->existsColumn($table_name, $column_old)) {
+			return Maintenance::ABNORMAL;
+		}
 		$status = $this->checkDB(
 			// TEST query
-			'DESCRIBE `' . $core->tables[$table_index] . '` `' . $column . '`',
+			'DESCRIBE `' . $table_name . '` `' . $column . '`',
 			// TEST output
 			array('type' => strtolower($new_type)),
 			// FIX query
-			'ALTER TABLE `' . $core->tables[$table_index] . '` CHANGE `' . $column . '` `' . $column . '` ' . $definition
+			'ALTER TABLE `' . $table_name . '` CHANGE `' . $column . '` `' . $column . '` ' . $definition
 		);
-		$this->lastMessage = "Changed type of column $column for tabke $table_index to tyoe " . strtoupper($new_type);
+		$this->lastMessage = "Changed type of column $column for table " . strtoupper($table_name) . " to tyoe " . strtoupper($new_type);
 		return $status;
 	}
 
-	public function checkDBRemove($table_index, $column)
+	public function checkDBRemove($table_name, $column)
 	{
-		global $core;
 		$status = $this->checkDB(
 			// TEST query
-			'DESCRIBE `' . $core->tables[$table_index] . '` `' . $column . '`',
+			'DESCRIBE `' . $table_name . '` `' . $column . '`',
 			// TEST output
 			NULL,
 			// FIX query
-			'ALTER TABLE `' . $core->tables[$table_index] . '` DROP COLUMN `' . $column . '`'
+			'ALTER TABLE `' . $table_name . '` DROP COLUMN `' . $column . '`'
 		);
-		$this->lastMessage = "Removed column $column for $table_index";
+		$this->lastMessage = "Removed column $column for " . strtoupper($table_name);
 		return $status;
 	}
 
-	public function dropKey($table_index, $key)
+	public function addKey($table_name, $key)
 	{
-		global $core;
-		$test = 'SHOW INDEX FROM `' . $core->tables[$table_index] . '` WHERE column_name = "' . $key . '"';
+		$test = 'SHOW INDEX FROM `' . $table_name . '` WHERE column_name = "' . $key . '"';
+		$test_out = array('table' => $table_name);
+		if ($this->testDB($test, $test_out)) {
+			$status = Maintenance::OK;
+		} else {
+			$fix = 'CREATE INDEX `' . $key . '` ON `' . $table_name . '` (`' . $key . '`)';
+			$this->dbh->query($fix);
+			if ($this->testDB($test, $test_out)) {
+				$status = Maintenance::FIXED;
+			} else {
+				$status = Maintenance::FIX_FAILED;
+			}
+		}
+		$this->lastMessage = 'Added KEY ' . $key . ' for ' . strtoupper($table_name);
+		return $status;
+	}
+
+	public function dropKey($table_name, $key)
+	{
+		$test = 'SHOW INDEX FROM `' . $table_name . '` WHERE column_name = "' . $key . '"';
 		$test_out = null;
 		if ($this->testDB($test, $test_out)) {
 			$status = Maintenance::OK;
 		} else {
-			$index_name = $core->dbh->getRow('SHOW INDEX FROM `' . $core->tables[$table_index] . '` WHERE column_name = "' . $key . '"')['key_name'];
-			$fix = 'ALTER TABLE `' . $core->tables[$table_index] . '` DROP INDEX ' . $index_name;
-			$core->dbh->query($fix);
+			$index_info = $this->dbh->getRow('SHOW INDEX FROM `' . $table_name . '` WHERE column_name = "' . $key . '"');
+			$index_info = array_change_key_case($index_info, CASE_LOWER);
+			$index_name = $index_info['key_name'];
+			$fix = 'ALTER TABLE `' . $table_name . '` DROP INDEX `' . $index_name . '`';
+			$this->dbh->query($fix);
 			if ($this->testDB($test, $test_out)) {
 				$status = Maintenance::FIXED;
 			} else {
 				$status = Maintenance::FIX_FAILED;
 			}
 		}
-		$this->lastMessage = 'Deleted KEY ' . $key . ' for ' . $table_index;
-		return $status;
-	}
-
-	public function addKey($table_index, $key)
-	{
-		global $core;
-		$test = 'SHOW INDEX FROM `' . $core->tables[$table_index] . '` WHERE column_name = "' . $key . '"';
-		$test_out = array('table' => $core->tables[$table_index]);
-		if ($this->testDB($test, $test_out)) {
-			$status = Maintenance::OK;
-		} else {
-			$fix = 'CREATE INDEX `' . $key . '` ON `' . $core->tables[$table_index] . '` (`' . $key . '`)';
-			$core->dbh->query($fix);
-			if ($this->testDB($test, $test_out)) {
-				$status = Maintenance::FIXED;
-			} else {
-				$status = Maintenance::FIX_FAILED;
-			}
-		}
-		$this->lastMessage = 'Added KEY ' . $key . ' for ' . $table_index;
+		$this->lastMessage = 'Deleted KEY ' . $key . ' for ' . strtoupper($table_name);
 		return $status;
 	}
 
 	public function updateDB($test, $test_out, $update)
 	{
-		global $core;
 		if (!$this->testDB($test, $test_out)) {
 			return Maintenance::OK;
 		} else {
-			$suc = $core->dbh->query($update);
+			$suc = $this->dbh->query($update);
 			if ($suc !== false) {
 				return Maintenance::UPDATED;
 			} else {
diff --git a/test/test4.php b/test/test4.php
new file mode 100644
index 0000000..7a995ec
--- /dev/null
+++ b/test/test4.php
@@ -0,0 +1,41 @@
+<?php
+
+require_once __DIR__.'/../src/DBmodel.php';
+require_once __DIR__.'/../src/Maintenance.php';
+
+$db = new \TPsoft\DBmodel\DBmodel('mysql:host=127.0.0.1;dbname=test;charset=utf8mb4', 'test', 'test');
+
+$maintenance = new \TPsoft\DBmodel\Maintenance($db);
+
+$suc = $maintenance->checkDBTable('users', '
+	`id` int(11) NOT NULL AUTO_INCREMENT,
+	`name` varchar(255) DEFAULT NULL,
+	`email` varchar(255) DEFAULT NULL,
+	PRIMARY KEY (`id`)
+');
+echo "\nCheckDBTable: "; var_dump($suc);
+
+$suc = $maintenance->checkDBAdd('users', 'password', 'varchar(255) DEFAULT NULL');
+echo "\nCheckDBAdd: "; var_dump($suc);
+
+$suc = $maintenance->existsColumn('users', 'email');
+echo "\nExistsColumn: "; var_dump($suc);
+
+$suc = $maintenance->checkDBRename('users', 'email', 'email_new', 'varchar(255) DEFAULT NULL');
+echo "\nCheckDBRename: "; var_dump($suc);
+
+$suc = $maintenance->checkDBRetype('users', 'email_new', 'varchar(128)', 'varchar(128) DEFAULT NULL AFTER `password`');
+echo "\nCheckDBRetype: "; var_dump($suc);
+
+$suc = $maintenance->checkDBRemove('users', 'email_new');
+echo "\nCheckDBRemove: "; var_dump($suc);
+
+$suc = $maintenance->addKey('users', 'name');
+echo "\nAddKey: "; var_dump($suc);
+
+$suc = $maintenance->dropKey('users', 'name');
+echo "\nDropKey: "; var_dump($suc);
+
+echo "\nDone\n\n";
+
+?>
\ No newline at end of file