Fixes #4492: Support PostgreSQL-specific syntax for `QueryBuilder::alterColumn()`

framework/CHANGELOG.md

@@ -32,6 +32,7 @@ Yii Framework 2 Change Log
 - Enh #4181: Added `yii\bootstrap\Modal::$headerOptions` and `yii\bootstrap\Modal::$footerOptions` (tuxoff, samdark)
 - Enh #4263: Added migration and SQL schema files for `yii\log\DbTarget` (samdark)
 - Enh #4457: Added support for using noscript for css files registered through asset bundles and Html helper (samdark)
+- Enh #4492: Support PostgreSQL-specific syntax for `QueryBuilder::alterColumn()` (qiangxue)
 - Enh #4739: Better display of exceptions when the response format is set as "raw" format (qiangxue)
 - Enh #5223: Query builder now supports selecting sub-queries as columns (qiangxue)
 - Enh #5367: Added `yii\grid\DataColumn::encodeLabel` (SDKiller)

framework/db/pgsql/QueryBuilder.php

@@ -150,14 +150,18 @@ class QueryBuilder extends \yii\db\QueryBuilder
      * @param string $type the new column type. The [[getColumnType()]] method will be invoked to convert abstract
      * column type (if any) into the physical one. Anything that is not recognized as abstract type will be kept
      * in the generated SQL. For example, 'string' will be turned into 'varchar(255)', while 'string not null'
-     * will become 'varchar(255) not null'.
+     * will become 'varchar(255) not null'. You can also use PostgreSQL-specific syntax such as `SET NOT NULL`.
      * @return string the SQL statement for changing the definition of a column.
      */
     public function alterColumn($table, $column, $type)
     {
+        // https://github.com/yiisoft/yii2/issues/4492
+        // http://www.postgresql.org/docs/9.1/static/sql-altertable.html
+        if (!preg_match('/^(DROP\s+DEFAULT|SET|RESET)\s+/i', $type)) {
+            $type = 'TYPE ' . $this->getColumnType($type);
+        }
         return 'ALTER TABLE ' . $this->db->quoteTableName($table) . ' ALTER COLUMN '
-            . $this->db->quoteColumnName($column) . ' TYPE '
-            . $this->getColumnType($type);
+            . $this->db->quoteColumnName($column) . ' ' . $type;
     }
 
     /**

tests/unit/framework/db/pgsql/PostgreSQLQueryBuilderTest.php

@@ -101,4 +101,25 @@ class PostgreSQLQueryBuilderTest extends QueryBuilderTest
             [ ['or not ilike', 'name', ['heyho', 'abc']], '"name" NOT ILIKE :qp0 OR "name" NOT ILIKE :qp1', [':qp0' => '%heyho%', ':qp1' => '%abc%'] ],
         ]);
     }
+
+    public function testAlterColumn()
+    {
+        $qb = $this->getQueryBuilder();
+
+        $expected = 'ALTER TABLE "foo1" ALTER COLUMN "bar" TYPE varchar(255)';
+        $sql = $qb->alterColumn('foo1', 'bar', 'varchar(255)');
+        $this->assertEquals($expected, $sql);
+
+        $expected = 'ALTER TABLE "foo1" ALTER COLUMN "bar" SET NOT null';
+        $sql = $qb->alterColumn('foo1', 'bar', 'SET NOT null');
+        $this->assertEquals($expected, $sql);
+
+        $expected = 'ALTER TABLE "foo1" ALTER COLUMN "bar" drop default';
+        $sql = $qb->alterColumn('foo1', 'bar', 'drop default');
+        $this->assertEquals($expected, $sql);
+
+        $expected = 'ALTER TABLE "foo1" ALTER COLUMN "bar" reset xyz';
+        $sql = $qb->alterColumn('foo1', 'bar', 'reset xyz');
+        $this->assertEquals($expected, $sql);
+    }
 }