DeleteTruncateTest.php

<?php

declare (strict_types=1);
namespace Drupal\KernelTests\Core\Database;

use Drupal\Core\Database\DatabaseExceptionWrapper;

/**
 * Tests delete and truncate queries.
 *
 * The DELETE tests are not as extensive, as all of the interesting code for
 * DELETE queries is in the conditional which is identical to the UPDATE and
 * SELECT conditional handling.
 *
 * The TRUNCATE tests are not extensive either, because the behavior of
 * TRUNCATE queries is not consistent across database engines. We only test
 * that a TRUNCATE query actually deletes all rows from the target table.
 *
 * @group Database
 */
class DeleteTruncateTest extends DatabaseTestBase {
    
    /**
     * Confirms that we can use a subselect in a delete successfully.
     */
    public function testSubselectDelete() : void {
        $num_records_before = $this->connection
            ->query('SELECT COUNT(*) FROM {test_task}')
            ->fetchField();
        $pid_to_delete = $this->connection
            ->query("SELECT * FROM {test_task} WHERE [task] = 'sleep' ORDER BY [tid]")
            ->fetchField();
        $subquery = $this->connection
            ->select('test', 't')
            ->fields('t', [
            'id',
        ])
            ->condition('t.id', [
            $pid_to_delete,
        ], 'IN');
        $delete = $this->connection
            ->delete('test_task')
            ->condition('task', 'sleep')
            ->condition('pid', $subquery, 'IN');
        $num_deleted = $delete->execute();
        $this->assertEquals(1, $num_deleted, 'Deleted 1 record.');
        $num_records_after = $this->connection
            ->query('SELECT COUNT(*) FROM {test_task}')
            ->fetchField();
        $this->assertEquals($num_records_before, $num_records_after + $num_deleted, 'Deletion adds up.');
    }
    
    /**
     * Confirms that we can delete a single record successfully.
     */
    public function testSimpleDelete() : void {
        $num_records_before = $this->connection
            ->query('SELECT COUNT(*) FROM {test}')
            ->fetchField();
        $num_deleted = $this->connection
            ->delete('test')
            ->condition('id', 1)
            ->execute();
        $this->assertSame(1, $num_deleted, 'Deleted 1 record.');
        $num_records_after = $this->connection
            ->query('SELECT COUNT(*) FROM {test}')
            ->fetchField();
        $this->assertEquals($num_records_before, $num_records_after + $num_deleted, 'Deletion adds up.');
    }
    
    /**
     * Confirms that we can truncate a whole table successfully.
     */
    public function testTruncate() : void {
        $num_records_before = $this->connection
            ->query("SELECT COUNT(*) FROM {test}")
            ->fetchField();
        $this->assertNotEmpty($num_records_before);
        $this->connection
            ->truncate('test')
            ->execute();
        $num_records_after = $this->connection
            ->query("SELECT COUNT(*) FROM {test}")
            ->fetchField();
        $this->assertEquals(0, $num_records_after, 'Truncate really deletes everything.');
    }
    
    /**
     * Confirms that we can truncate a whole table while in transaction.
     */
    public function testTruncateInTransaction() : void {
        $num_records_before = $this->connection
            ->select('test')
            ->countQuery()
            ->execute()
            ->fetchField();
        $this->assertGreaterThan(0, $num_records_before, 'The table is not empty.');
        $transaction = $this->connection
            ->startTransaction('test_truncate_in_transaction');
        $this->connection
            ->insert('test')
            ->fields([
            'name' => 'Freddie',
            'age' => 45,
            'job' => 'Great singer',
        ])
            ->execute();
        $num_records_after_insert = $this->connection
            ->select('test')
            ->countQuery()
            ->execute()
            ->fetchField();
        $this->assertEquals($num_records_before + 1, $num_records_after_insert);
        $this->connection
            ->truncate('test')
            ->execute();
        // Checks that there are no records left in the table, and transaction is
        // still active.
        $this->assertTrue($this->connection
            ->inTransaction());
        $num_records_after = $this->connection
            ->select('test')
            ->countQuery()
            ->execute()
            ->fetchField();
        $this->assertEquals(0, $num_records_after);
        // Close the transaction, and check that there are still no records in the
        // table.
        $transaction = NULL;
        $this->assertFalse($this->connection
            ->inTransaction());
        $num_records_after = $this->connection
            ->select('test')
            ->countQuery()
            ->execute()
            ->fetchField();
        $this->assertEquals(0, $num_records_after);
    }
    
    /**
     * Confirms that transaction rollback voids a truncate operation.
     */
    public function testTruncateTransactionRollback() : void {
        $num_records_before = $this->connection
            ->select('test')
            ->countQuery()
            ->execute()
            ->fetchField();
        $this->assertGreaterThan(0, $num_records_before, 'The table is not empty.');
        $transaction = $this->connection
            ->startTransaction('test_truncate_in_transaction');
        $this->connection
            ->insert('test')
            ->fields([
            'name' => 'Freddie',
            'age' => 45,
            'job' => 'Great singer',
        ])
            ->execute();
        $num_records_after_insert = $this->connection
            ->select('test')
            ->countQuery()
            ->execute()
            ->fetchField();
        $this->assertEquals($num_records_before + 1, $num_records_after_insert);
        $this->connection
            ->truncate('test')
            ->execute();
        // Checks that there are no records left in the table, and transaction is
        // still active.
        $this->assertTrue($this->connection
            ->inTransaction());
        $num_records_after = $this->connection
            ->select('test')
            ->countQuery()
            ->execute()
            ->fetchField();
        $this->assertEquals(0, $num_records_after);
        // Roll back the transaction, and check that we are back to status before
        // insert and truncate.
        $transaction->rollBack();
        $this->assertFalse($this->connection
            ->inTransaction());
        $num_records_after = $this->connection
            ->select('test')
            ->countQuery()
            ->execute()
            ->fetchField();
        $this->assertEquals($num_records_before, $num_records_after);
    }
    
    /**
     * Confirms that we can delete a single special column name record successfully.
     */
    public function testSpecialColumnDelete() : void {
        $num_records_before = $this->connection
            ->query('SELECT COUNT(*) FROM {select}')
            ->fetchField();
        $num_deleted = $this->connection
            ->delete('select')
            ->condition('update', 'Update value 1')
            ->execute();
        $this->assertEquals(1, $num_deleted, 'Deleted 1 special column record.');
        $num_records_after = $this->connection
            ->query('SELECT COUNT(*) FROM {select}')
            ->fetchField();
        $this->assertEquals($num_records_before, $num_records_after + $num_deleted, 'Deletion adds up.');
    }
    
    /**
     * Deleting from a not existing table throws a DatabaseExceptionWrapper.
     */
    public function testDeleteFromNonExistingTable() : void {
        $this->expectException(DatabaseExceptionWrapper::class);
        $this->connection
            ->delete('a-table-that-does-not-exist')
            ->execute();
    }
    
    /**
     * Truncating a not existing table throws a DatabaseExceptionWrapper.
     */
    public function testTruncateNonExistingTable() : void {
        $this->expectException(DatabaseExceptionWrapper::class);
        $this->connection
            ->truncate('a-table-that-does-not-exist')
            ->execute();
    }

}