The fixed issues were exposed when fixing the incoming issues from th…

src/Sql/AbstractSql.php

@@ -35,8 +35,8 @@
 use function vsprintf;
 
 abstract class AbstractSql implements SqlInterface
-{
-    public ?object $subject = null;
+    {
+    protected SqlInterface|PreparableSqlInterface|null $subject = null;
 
     /**
      * Specifications for Sql String generation

src/Sql/Ddl/AlterTable.php

@@ -10,7 +10,7 @@
 
 use function array_key_exists;
 
-class AlterTable extends AbstractSql implements SqlInterface
+class AlterTable extends AbstractSql
 {
     final public const ADD_COLUMNS = 'addColumns';
 

src/Sql/Ddl/CreateTable.php

@@ -10,7 +10,7 @@
 
 use function array_key_exists;
 
-class CreateTable extends AbstractSql implements SqlInterface
+class CreateTable extends AbstractSql
 {
     final public const COLUMNS = 'columns';
 

src/Sql/Ddl/DropTable.php

@@ -8,7 +8,7 @@
 use PhpDb\Sql\AbstractSql;
 use PhpDb\Sql\TableIdentifier;
 
-class DropTable extends AbstractSql implements SqlInterface
+class DropTable extends AbstractSql
 {
     final public const TABLE = 'table';
 

src/Sql/Platform/PlatformDecoratorInterface.php

@@ -4,7 +4,12 @@
 
 namespace PhpDb\Sql\Platform;
 
+use PhpDb\Sql\PreparableSqlInterface;
+use PhpDb\Sql\SqlInterface;
+
 interface PlatformDecoratorInterface
 {
-    public function setSubject(?object $subject): PlatformDecoratorInterface;
+    public function setSubject(
+        SqlInterface|PreparableSqlInterface|null $subject
+    ): PlatformDecoratorInterface;
 }