Reorganize documentation and stream line it.

Previously we had one massive disorganized page. Now I've tried to
separate the docs up into smaller files. This helps with navigation
and scanning short documents is easier than long ones.

Author: markstory

docs/en/executing-queries.rst

@@ -0,0 +1,134 @@
+Executing Queries
+#################
+
+Queries can be executed with the ``execute()`` and ``query()`` methods. The
+``execute()`` method returns the number of affected rows whereas the
+``query()`` method returns the result as a
+`CakePHP Statement <https://book.cakephp.org/5/en/orm/database-basics.html#interacting-with-statements>`_. Both methods
+accept an optional second parameter ``$params`` which is an array of elements,
+and if used will cause the underlying connection to use a prepared statement::
+
+    <?php
+
+    use Migrations\BaseMigration;
+
+    class MyNewMigration extends BaseMigration
+    {
+        /**
+         * Migrate Up.
+         */
+        public function up(): void
+        {
+            // execute()
+            $count = $this->execute('DELETE FROM users'); // returns the number of affected rows
+
+            // query()
+            $stmt = $this->query('SELECT * FROM users'); // returns PDOStatement
+            $rows = $stmt->fetchAll(); // returns the result as an array
+
+            // using prepared queries
+            $count = $this->execute('DELETE FROM users WHERE id = ?', [5]);
+            $stmt = $this->query('SELECT * FROM users WHERE id > ?', [5]); // returns PDOStatement
+            $rows = $stmt->fetchAll();
+        }
+
+        /**
+         * Migrate Down.
+         */
+        public function down(): void
+        {
+
+        }
+    }
+
+Fetching Rows
+=============
+
+There are two methods available to fetch rows. The ``fetchRow()`` method will
+fetch a single row, whilst the ``fetchAll()`` method will return multiple rows.
+Both methods accept raw SQL as their only parameter::
+
+    <?php
+
+    use Migrations\BaseMigration;
+
+    class MyNewMigration extends BaseMigration
+    {
+        /**
+         * Migrate Up.
+         */
+        public function up(): void
+        {
+            // fetch a user
+            $row = $this->fetchRow('SELECT * FROM users');
+
+            // fetch an array of messages
+            $rows = $this->fetchAll('SELECT * FROM messages');
+        }
+
+        /**
+         * Migrate Down.
+         */
+        public function down(): void
+        {
+
+        }
+    }
+
+Inserting Data
+==============
+
+Migrations makes it easy to insert data into your tables. Whilst this feature is
+intended for the :doc:`seed feature <seeding>`, you are also free to use the
+insert methods in your migrations::
+
+    <?php
+
+    use Migrations\BaseMigration;
+
+    class NewStatus extends BaseMigration
+    {
+        /**
+         * Migrate Up.
+         */
+        public function up(): void
+        {
+            $table = $this->table('status');
+
+            // inserting only one row
+            $singleRow = [
+                'id'    => 1,
+                'name'  => 'In Progress'
+            ];
+
+            $table->insert($singleRow)->saveData();
+
+            // inserting multiple rows
+            $rows = [
+                [
+                  'id'    => 2,
+                  'name'  => 'Stopped'
+                ],
+                [
+                  'id'    => 3,
+                  'name'  => 'Queued'
+                ]
+            ];
+
+            $table->insert($rows)->saveData();
+        }
+
+        /**
+         * Migrate Down.
+         */
+        public function down(): void
+        {
+            $this->execute('DELETE FROM status');
+        }
+    }
+
+.. note::
+
+    You cannot use the insert methods inside a `change()` method. Please use the
+    `up()` and `down()` methods.
+