proceed further with beans

beans/OrderBy.php

@@ -0,0 +1,9 @@
+<?php
+namespace DatabaseHelper\beans;
+
+use DatabaseHelper\enums\Order;
+
+class OrderBy {
+    public string $col;
+    public Order $order;
+}

beans/Schema.php

@@ -10,19 +10,43 @@ use http\Exception\InvalidArgumentException;
 class Schema
 {
     public string $name = '';
-    public Primary $primary;
+    public Primary $id;
 
     /**
      * @var array<string, Column>
      */
-    public array $columns = [];
+    public array $cols = [];
 
     /**
      * @var array<string, Reference>
      */
-    public array $references = [];
+    public array $refs = [];
 
     public Engine $engine = Engine::INNODB;
     public Charset $charset = Charset::UTF8;
     public Collation $collation = Collation::UTF8_GENERAL_CI;
+
+    public function existsCol(string $name): bool {
+        return isset($this->cols[$name]);
+    }
+
+    public function reqCol(string $name): void {
+        if (!$this->existsCol($name))
+            throw new InvalidArgumentException("Column $name does not exist in schema $this->name.");
+    }
+
+    public function getCol(string $name): Column {
+        return $this->cols[$name];
+    }
+
+    public function existsRef(Schema $other): bool {
+        $otherId = $other->id;
+        // TODO
+        return true;
+    }
+
+    public function reqRef(Schema $other): void {
+        if (!$this->existsRef($other))
+            throw new InvalidArgumentException("A reference to $other->name is not defined in  $this->name.");
+    }
 }