corrections, improved test example for query_prepared method, some code coverage

Author: TheTechsTech

README.md

@@ -190,6 +190,8 @@ foreach ($result as $row) {
 }
 ```
 
+>Note: `query_prepared()` example works correctly for MySQL, the other drivers will return full query result statement. Will not be stored in `last_result`.
+
 ## For Authors and **[Contributors](https://github.com/ezSQL/ezsql/blob/master/CONTRIBUTORS.md)**
 
 ## Contributing

lib/ezFunctions.php

@@ -83,12 +83,12 @@ function index(string $indexName, ...$indexKeys)
         return \column(\INDEX, $indexName, ...$indexKeys);
     }
 
-    function add(string $columnName, ...$datatype)
+    function addColumn(string $columnName, ...$datatype)
     {
         return \column(\ADD, $columnName, ...$datatype);
     }
 
-    function drop(string $columnName, ...$data)
+    function dropColumn(string $columnName, ...$data)
     {
         return \column(\DROP, $columnName, ...$data);
     }

tests/ezFunctionsTest.php

@@ -11,10 +11,82 @@ protected function setUp(): void
         \clearInstance();
     }
 
+    /**
+     * @test getInstance 
+     */
+    public function testGetInstance()
+    {
+        $this->assertNull(getInstance());
+    }
+    
+    /**
+     * @test getVendor 
+     */
+    public function testGetVendor()
+    {
+        $this->assertNull(getVendor());
+    }
+
+    /**
+     * @test column 
+     */
+    public function testColumn()
+    {
+        $this->assertFalse(column('string', VARCHAR, 32));
+    }
+    
+    /**
+     * @test primary 
+     */
+    public function testPrimary()
+    {
+        $this->assertFalse(primary('label', 'column'));
+    }
+
+    /**
+     * @test foreign 
+     */
+    public function testForeign()
+    {
+        $this->assertFalse(foreign('label', 'column'));
+    }
+
+    /**
+     * @test unique 
+     */
+    public function testUnique()
+    {
+        $this->assertFalse(unique('label', 'column'));
+    }
+
+    /**
+     * @test index 
+     */
+    public function testIndex()
+    {
+        $this->assertFalse(index('label', 'column'));
+    }
+
+    /**
+     * @test addColumn 
+     */
+    public function testAddColumn()
+    {
+        $this->assertFalse(addColumn('column', VARCHAR, 32));
+    }
+
+    /**
+     * @test dropColumn 
+     */
+    public function testDropColumn()
+    {
+        $this->assertFalse(dropColumn('column', 'column'));
+    }
+
     /**
      * @test eq 
      */
-    public function testeq()
+    public function testEq()
     {
         $this->assertInternalType('array',eq('field', 'data'));
         $this->assertArraySubset([1 => EQ], eq('field', 'data'));

tests/mysqli/mysqliTest.php

@@ -515,8 +515,18 @@ public function testQuery_prepared() {
                 column('prepare_key', VARCHAR, 50))
         );
 
-        $result = $this->object->query_prepared('INSERT INTO unit_test( id, prepare_key ) VALUES( 9, ? )', ['test 1']);
+        $result = $this->object->query_prepared('INSERT INTO unit_test( id, prepare_key ) VALUES( ?, ? )', [ 9, 'test 1']);
         $this->assertEquals(1, $result);
+
+        $this->object->query_prepared('SELECT prepare_key FROM unit_test WHERE id = ?', [9]);
+        $query = $this->object->queryResult();
+        
+        foreach($query as $row) {
+            $result = $row->prepare_key;
+        }
+
+        $this->assertEquals('test 1', $this->object->queryResult()[0]->prepare_key);
+        $this->assertEquals('test 1', $result);
     } // testQuery_prepared
 
     /**