Abstract: Provided are a doubleheader logging methods of a slotted page and a database apparatuses. The method of doubleheader logging of a slotted page performed by a database apparatus includes determining a valid slot header among a first slot header and a second slot header of a page to select a slot header; selecting a valid slot header according to the determination result; and performing a transaction based on the selected valid slot header.

Abstract: Provided is a database journaling method and apparatus for storing a log file in a storing apparatus by performing a lesser number of record commands to decrease a volume of data to be input and output by the storing apparatus, and the database journaling method may include determining whether a database is changed based on an operation performed on data in the database, generating a log file including log entries for the database when the database is changed, and performing journaling on the database by storing the generated log file in a storing apparatus, wherein each of the log entries includes a log record in which the data associated with a change of the database is stored, and metadata for the log record is recorded in a predetermined area embedded in the log record.

Abstract: A data storing method performed by a data storing apparatus according to an exemplary embodiment of the present invention includes a step of calling insert operation for storing first data in a first page having a space for storing data, a step of checking whether overflow in which there is no space for storing the first data in the first page occurs, a step of checking whether the overflow occurs in the first page and dead data is stored in the first page, and a step of generating an overflow buffer page to store the first data in the overflow buffer page when the overflow occurs in the first page and the dead data is stored in the first page and there is a transaction accessing the dead data.

Abstract: Provided are a doubleheader logging methods of a slotted page and a database apparatuses. The method of doubleheader logging of a slotted page performed by a database apparatus includes determining a valid slot header among a first slot header and a second slot header of a page to select a slot header; selecting a valid slot header according to the determination result; and performing a transaction based on the selected valid slot header.

Abstract: A data storing method performed by a data storing apparatus according to an exemplary embodiment of the present invention includes a step of calling insert operation for storing first data in a first page having a space for storing data, a step of checking whether overflow in which there is no space for storing the first data in the first page occurs, a step of checking whether the overflow occurs in the first page and dead data is stored in the first page, and a step of generating an overflow buffer page to store the first data in the overflow buffer page when the overflow occurs in the first page and the dead data is stored in the first page and there is a transaction accessing the dead data.

Abstract: Provided is a database journaling method and apparatus for storing a log file in a storing apparatus by performing a lesser number of record commands to decrease a volume of data to be input and output by the storing apparatus, and the database journaling method may include determining whether a database is changed based on an operation performed on data in the database, generating a log file including log entries for the database when the database is changed, and performing journaling on the database by storing the generated log file in a storing apparatus, wherein each of the log entries includes a log record in which the data associated with a change of the database is stored, and metadata for the log record is recorded in a predetermined area embedded in the log record.

Abstract: Disclosed is a protection method and device for metadata of a file. The protection method may include pre-allocating, to a storage device, a preset quantity of initialized blocks for a journal file and journaling, in the storage device, updated metadata of the journal file by calling a data synchronization function.