File indexing completed on 2025-03-09 03:54:59

 /* ============================================================
  *
  * This file is a part of digiKam project
  * https://www.digikam.org
  *
  * Date        : 2010-10-12
  * Description : Convenience object for grouping face database operations
  *
  * SPDX-FileCopyrightText: 2010 by Marcel Wiesweg <marcel dot wiesweg at gmx dot de>
  *
  * SPDX-License-Identifier: GPL-2.0-or-later
  *
  * ============================================================ */
 
 #ifndef DIGIKAM_FACE_DB_OPERATION_GROUP_H
 #define DIGIKAM_FACE_DB_OPERATION_GROUP_H
 
 namespace Digikam
 {
 
 class FaceDbAccess;
 
 /**
  * When you intend to execute a number of write operations to the database,
  * group them while holding a FaceDbOperationGroup.
  * For some database systems (SQLite), keeping a transaction across write operations
  * occurring in short time results in enormous speedup (800x).
  * For system that do not need this optimization, this class is a no-op.
  */
 class FaceDbOperationGroup
 {
 public:
 
     /**
      * Retrieve a FaceDbAccess object each time when constructing and destructing.
      */
     FaceDbOperationGroup();
 
     /**
      * Use an existing FaceDbAccess object, which must live as long as this object exists.
      */
     explicit FaceDbOperationGroup(FaceDbAccess* const dbAccess);
 
     ~FaceDbOperationGroup();
 
     /**
      * This will - if a transaction is held - commit the transaction and acquire a new one.
      * This may improve concurrent access.
      */
     void lift();
 
     void setMaximumTime(int msecs);
 
     /**
      * Resets to 0 the time used by allowLift()
      */
     void resetTime();
 
     /**
      * Allows to lift(). The transaction will be lifted if the time set by setMaximumTime()
      * has expired.
      */
     void allowLift();
 
 private:
 
     // Disable
     FaceDbOperationGroup(const FaceDbOperationGroup&)            = delete;
     FaceDbOperationGroup& operator=(const FaceDbOperationGroup&) = delete;
 
 private:
 
     class Private;
     Private* const d;
 };
 
 } // namespace Digikam
 
 #endif // DIGIKAM_FACE_DB_OPERATION_GROUP_H