allow data sources to provide smaller integers based on storage requirements

lib/Cake/Model/Datasource/Database/Mysql.php

@@ -117,6 +117,10 @@ class Mysql extends DboSource {
 		'text' => array('name' => 'text'),
 		'biginteger' => array('name' => 'bigint', 'limit' => '20'),
 		'integer' => array('name' => 'int', 'limit' => '11', 'formatter' => 'intval'),
+		'integer/4' => array('name' => 'int', 'limit' => '11', 'formatter' => 'intval'),
+		'integer/3' => array('name' => 'mediumint', 'limit' => '9', 'formatter' => 'intval'),
+		'integer/2' => array('name' => 'smallint', 'limit' => '6', 'formatter' => 'intval'),
+		'integer/1' => array('name' => 'tinyint', 'limit' => '4', 'formatter' => 'intval'),
 		'float' => array('name' => 'float', 'formatter' => 'floatval'),
 		'decimal' => array('name' => 'decimal', 'formatter' => 'floatval'),
 		'datetime' => array('name' => 'datetime', 'format' => 'Y-m-d H:i:s', 'formatter' => 'date'),
@@ -369,6 +373,10 @@ class Mysql extends DboSource {
 					$fields[$column->Field]['charset'] = $charset;
 				}
 			}
+			$storage = $this->storageRequirement($column->Type);
+			if (is_numeric($storage)) {
+				$fields[$column->Field]['storage'] = $storage;
+			}
 		}
 		$this->_cacheDescription($key, $fields);
 		$cols->closeCursor();
@@ -810,6 +818,36 @@ class Mysql extends DboSource {
 		return 'text';
 	}
 
+/**
+ * Gets the storage requirement of a database-native column description, or null if unknown or N/A
+ *
+ * @param string $real Real database-layer column type (i.e. "varchar(255)")
+ * @return mixed An integer representing the storage requirement of the column in bytes, or null if unknown or N/A.
+ */
+	public function storageRequirement($real) {
+		if (is_array($real)) {
+			$col = $real['name'];
+		} else {
+			$col = $real;
+			if (strpos($col, '(') !== false) {
+				list($col, $vals) = explode('(', $col);
+			}
+		}
+
+		// Base on Storage Requirements for Numeric Types
+		// https://dev.mysql.com/doc/refman/5.7/en/storage-requirements.html
+		if ($col === 'tinyint') {
+			return 1;
+		}
+		if ($col === 'smallint') {
+			return 2;
+		}
+		if ($col === 'mediumint') {
+			return 3;
+		}
+		return null;
+	}
+
 /**
  * {@inheritDoc}
  */

lib/Cake/Model/Datasource/DboSource.php

@@ -3246,6 +3246,16 @@ class DboSource extends DataSource {
 		return (int)$length;
 	}
 
+/**
+ * Gets the storage requirement of a database-native column description, or null if unknown or N/A
+ *
+ * @param string $real Real database-layer column type (i.e. "varchar(255)")
+ * @return mixed An integer representing the storage requirement of the column in bytes, or null if unknown or N/A.
+ */
+	public function storageRequirement($real) {
+		return null;
+	}
+
 /**
  * Translates between PHP boolean values and Database (faked) boolean values
  *
@@ -3459,12 +3469,16 @@ class DboSource extends DataSource {
 			return null;
 		}
 
+		// if a storage requirement in bytes was set, try it first (i.e. 'integer/4' before 'integer')
+		if (isset($storage) && isset($this->columns[$type . '/' . $storage])) {
+			$real = $this->columns[$type . '/' . $storage];
+		} else {
 			if (!isset($this->columns[$type])) {
 				trigger_error(__d('cake_dev', 'Column type %s does not exist', $type), E_USER_WARNING);
 				return null;
 			}
-
 			$real = $this->columns[$type];
+		}
 		$out = $this->name($name) . ' ' . $real['name'];
 
 		if (isset($column['length'])) {

lib/Cake/Test/Case/Model/Datasource/Database/MysqlTest.php

@@ -389,6 +389,36 @@ class MysqlTest extends CakeTestCase {
 		$expected = '`testName`  CHARACTER SET utf8 COLLATE utf8_unicode_ci DEFAULT NULL';
 		$this->assertEquals($expected, $result);
 		$this->Dbo->columns = $restore;
+
+		$data = array(
+			'name' => 'testName',
+			'type' => 'integer',
+			'storage' => 1
+		);
+		$result = $this->Dbo->buildColumn($data);
+		$expected = '`testName` tinyint(4)';
+		$this->assertEquals($expected, $result);
+		$this->Dbo->columns = $restore;
+
+		$data = array(
+			'name' => 'testName',
+			'type' => 'integer',
+			'storage' => 2
+		);
+		$result = $this->Dbo->buildColumn($data);
+		$expected = '`testName` smallint(6)';
+		$this->assertEquals($expected, $result);
+		$this->Dbo->columns = $restore;
+
+		$data = array(
+			'name' => 'testName',
+			'type' => 'integer',
+			'storage' => 3
+		);
+		$result = $this->Dbo->buildColumn($data);
+		$expected = '`testName` mediumint(9)';
+		$this->assertEquals($expected, $result);
+		$this->Dbo->columns = $restore;
 	}
 
 /**
@@ -526,6 +556,18 @@ class MysqlTest extends CakeTestCase {
 		$expected = 'boolean';
 		$this->assertEquals($expected, $result);
 
+		$result = $this->Dbo->column('tinyint(4)');
+		$expected = 'integer';
+		$this->assertEquals($expected, $result);
+
+		$result = $this->Dbo->column('smallint');
+		$expected = 'integer';
+		$this->assertEquals($expected, $result);
+
+		$result = $this->Dbo->column('mediumint');
+		$expected = 'integer';
+		$this->assertEquals($expected, $result);
+
 		$result = $this->Dbo->column('boolean');
 		$expected = 'boolean';
 		$this->assertEquals($expected, $result);
@@ -3092,6 +3134,29 @@ SQL;
 		$this->assertSame($expected, $result);
 	}
 
+/**
+ * test storageRequirement method
+ *
+ * @return void
+ */
+	public function testStorageRequirement () {
+		$result = $this->Dbo->storageRequirement('varchar(255)');
+		$expected = null;
+		$this->assertSame($expected, $result);
+
+		$result = $this->Dbo->storageRequirement('mediumint');
+		$expected = 3;
+		$this->assertSame($expected, $result);
+
+		$result = $this->Dbo->storageRequirement('smallint');
+		$expected = 2;
+		$this->assertSame($expected, $result);
+
+		$result = $this->Dbo->storageRequirement('tinyint');
+		$expected = 1;
+		$this->assertSame($expected, $result);
+	}
+
 /**
  * testBuildIndex method
  *