WIP on docs and added basic enums supports

src/Query/Show.php

@@ -0,0 +1,45 @@
+<?php
+
+namespace Ulmus\Query;
+
+class Show extends Fragment {
+
+    public int $order = -100;
+
+    const SQL_TOKEN = "SHOW";
+
+    const SQL_TOKEN_FROM = "FROM";
+
+    const SQL_SHOW_DATABASES = "DATABASES";
+
+    const SQL_SHOW_TABLES = "TABLES";
+
+    public string $show;
+
+    public string $from;
+
+    public string $in;
+
+    public function set(string $show, ? string $from = null, ? string $in = null) : self
+    {
+        $this->show = $show;
+
+        if ( $from !== null ) {
+            $this->from = $from;
+        }
+
+        if ( $in !== null ) {
+            $this->in = $in;
+        }
+        
+        return $this;
+    }
+
+    public function render() : string
+    {
+        return $this->renderSegments([
+            static::SQL_TOKEN, $this->show,
+        ] + ( ! empty($this->from) ? [ static::SQL_TOKEN_FROM, $this->from ] : [] ) + ( ! empty($this->in) ? [ static::SQL_TOKEN_IN, $this->in ] : [] ) );
+    }
+
+}