Fix drop table if exists for Oracle (#920)

Author: mvorisek

src/Persistence/Sql/Exception.php

@@ -4,9 +4,11 @@
 
 namespace Atk4\Data\Persistence\Sql;
 
+use Atk4\Data\Exception as BaseException;
+
 /**
  * All exceptions generated by DSQL use this class.
  */
-class Exception extends \Atk4\Core\Exception
+class Exception extends BaseException
 {
 }

src/Schema/Migration.php

@@ -4,7 +4,7 @@
 
 namespace Atk4\Data\Schema;
 
-use Atk4\Core\Exception;
+use Atk4\Data\Exception;
 use Atk4\Data\Field;
 use Atk4\Data\FieldSqlExpression;
 use Atk4\Data\Model;
@@ -98,7 +98,9 @@ public function create(): self
 
     public function drop(): self
     {
-        $this->getSchemaManager()->dropTable($this->getDatabasePlatform()->quoteSingleIdentifier($this->table->getName()));
+        $this->getSchemaManager()
+            ->dropTable($this->getDatabasePlatform()->quoteSingleIdentifier($this->table->getName()));
+
         $this->createdTableNames = array_diff($this->createdTableNames, [$this->table->getName()]);
 
         return $this;
@@ -111,6 +113,19 @@ public function dropIfExists(): self
         } catch (\Doctrine\DBAL\Exception|\Doctrine\DBAL\DBALException $e) {
         }
 
+        $this->createdTableNames = array_diff($this->createdTableNames, [$this->table->getName()]);
+
+        // OracleSchemaManager::dropTable() called in self::drop() above tries to drop AI,
+        // but if AI trigger is not present, AI sequence is not dropped
+        // https://github.com/doctrine/dbal/issues/4997
+        if ($this->getDatabasePlatform() instanceof OraclePlatform) {
+            $dropTriggerSql = $this->getDatabasePlatform()->getDropAutoincrementSql($this->table->getName())[1];
+            try {
+                $this->connection->expr($dropTriggerSql)->execute();
+            } catch (Exception $e) {
+            }
+        }
+
         return $this;
     }
 
@@ -152,6 +167,7 @@ public function id(string $name = 'id'): self
         $options = [
             'type' => 'integer',
             'ref_type' => self::REF_TYPE_PRIMARY,
+            'mandatory' => true,
         ];
 
         $this->field($name, $options);

src/Schema/TestCase.php

@@ -130,12 +130,12 @@ public function setDb(array $dbData, bool $importData = true): void
         foreach ($dbData as $tableName => $data) {
             $migrator = $this->createMigrator()->table($tableName);
 
-            // drop table if exists but only if it was created during this test
+            // drop table if already created but only if it was created during this test
             foreach ($this->createdMigrators as $migr) {
                 if ($migr->connection === $this->db->connection) {
                     foreach ($migr->getCreatedTableNames() as $t) {
                         if ($t === $tableName) {
-                            $migrator->dropIfExists();
+                            $migrator->drop();
 
                             break 2;
                         }