KR930009854B1 - Database backing-up & restoring method - Google Patents

Abstract

The method provides the backup and recovery of data base which guarantees the no-defect of data in the data base management system. The method comprises; the first step which makes the transmit log to the operation and maintenance processor, receives the log file, and stores the log file in the corresponding log file; the second step which fetches logs from the log file and applies logs into the corresponding PLD when the backup is requested; the third step which requires the PLD and log file from disk to memory if the restarting is required; and the fourth step which applies log into PLD and finish the recovery process.

Description

Database Backup and Recovery Method in DBMS of Electronic Switching System

1 is a structural diagram of a database backup and recovery function of a DBMS of an electronic switching system of the present invention.

2 is a block diagram configuration and message flow structure for implementing a database backup and recovery function in the DBMS of the electronic switchboard.

3 is an overall flowchart of the database backup and recovery process of the present invention DBMS.

* Explanation of symbols for main parts of the drawings

ASS: Access Switching Suvsystem

INS: Interconnection Network Subsystem

CCS: Central Control Sybsystem

DBMS: Data Base Management System

DBSG: Data Base Supporting Group

DBBG: Data Base Backup Group

DBKG: Data Base Kernel Group

CDB: Central Data Base in disk

LDB: Local Data Base in main Memory

The present invention relates to a method of database backup and recovery in a DBMS (Database Management System) of an electronic switchboard.

In most past SPC (Stored Program Control) exchanges, data was defined for each application program, so it was possible to respond quickly.However, there was too much redundant data, making it difficult to maintain and operate. In some cases, it was inconvenient to take several steps to obtain necessary information because it is expressed in a way to maximize the efficiency in the process. Therefore, it is necessary to have a DBMS that comprehensively manages the data used by all applications in one place to reduce the redundant data so that maintenance and operation management can be performed efficiently and to obtain necessary information easily.

In order to efficiently maintain and manage the data, the data used by the applications are collected and maintained in one place so that the applications that the applications are searching for, modifying and even running the application can be Even if it is down and restarted, it should always be able to provide accurate and consistent data to the application.

Accordingly, it is an object of the present invention to provide a method for backing up and restoring a database that guarantees no-deletion of data in a DBMS of an electronic switchboard.

In order to achieve the above object, the present invention is equipped with a database management system (DBMS) consisting of three blocks of DBBG (Data Base Backup Group), DBSG (Data Base Supporting Group) and DBKG (Data Base Kernel Group) OMP (Operation and Maintenance Processor) and all of the components of the database management system that have a number of other processors (ASP, INP, MMP) with only DBSG (Data Base Supporting Group) and DBKL (Data Base Kernel Group) A method for backing up and restoring a database applied to an electronic exchange, comprising: a first step of receiving a backup data change request from an application program, making a change in a log, and storing the change in a log file; A second step of backing up the contents of the loaded corresponding load file to the corresponding database on the disk, and receiving a recovery request from the downed processor after the second step. Be done by having a fourth step of applying a third phase, the logs in the log file, after the third step of requesting the information in the database in the memory for the log file.

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

1 is a structural diagram of a DBMS (Data Base Management System) configured to provide a database backup and recovery function of an electronic switch system.

The electronic switch to which the present invention is applied has an access switching suvsystem (ASS) that performs distributed call processing, an INS (interconnection network subsystem) that performs centralized call processing, and a centralization function of operation and maintenance. It consists of three sub-systems of the Central Control Sybsystem (CCS). DBMS, a system that handles data manipulation (retrieval, change), data integrity, data security, data backup, and data recovery functions, exists in all processors, and consists of DBSG, DBBG, and DBKG blocks according to each processing function. It is.

DBSG (Data Base Supporting Group) provides the database access request function required by the application, logs the changed contents for the data that needs to be backed up, and restores the database of the processor to the state before the processor was down when the processor was down. It is a block that performs communication function between DBMSs to access the database existing in other processors. DBBG (Data Base Backup Group) provides the ability to maintain a copy of the database in main memory on disk, i.e. backing up, writing logs to a log file, and sending log file information for data recovery when the processor is down. It is a block that performs redundant relation processing. The DBKG (Data Base Kernel Group) is responsible for receiving data access requests and classifying them according to the type of relation, manipulating data, concurrent access control, manipulating distributed relations, and manipulating relations that exist only on disk. Block.

2 is a structural diagram showing the configuration and flow of messages between related blocks for implementing a database backup and recovery function in a DBMS of an electronic switchgear.

The DBMS of the electronic switchboard has different components of the DBMS according to the function of the processor.The DBMS of the OMP (Operation and Maintenance-ance Processor) processor is composed of blocks of DBSG, DBBG, DBKG, and other processors (ASP, INP, DBMS of MMP is composed of DBSG and DBKG.

Since only OMP processors have disks, DBBG blocks that require disk access for data backup and recovery only exist on OMP processors.

When the DBSG block receives a data change request from an application, the DBSG block logs the changes in the log record format so that the changes can be applied to the processor load data (PLD), which is a copy of the database on disk, when the type of relation to be changed is DKB (Disk Backup). To send the log to the DBBG block for processing. DBBG then stores this log in a log file on disk and, upon a backup request, obtains the log file of the requested processor required by the backup, and applies the log to the corresponding PLD on disk, thereby saving the contents of the database and the disk in memory. Ensure that the contents of the PLDs in the directory are consistent.

On the other hand, if a processor goes down, the database is lost in memory, so it must be restored to maintain the state before the processor went down. The system loader stores the PLD of the processor on disk and the log files of the processor that have not been backed up. The PL loader, the processor loader, then requests the DBSG block to perform its recovery function. Then, the DBSG block receives log file information from the DBBG block, restores the database to the state before the processor was down, and executes the PL block to execute applications installed in the processor.

3 is a general flow diagram of a method of database backup and recovery in a DBMS of an electronic switchgear.

Database backup changes the backup relation in an application to receive a change buffer containing the changes (1), create a log that can be applied to the PLD, a copy of the database on disk, and send the log to the OPM processor (2). Receive and store the log in the log file (3), then backup request (backup request by the operator's MMC command, backup request when the log file size threshold is exceeded, and the most frequent to reduce the overall load on the system. Automatically request backups (4) retrieve logs from the processor's log file (5), apply logs to the corresponding PLD on disk (6), and terminate the database backup process when the log application is complete. (7). Database recovery receives a reboot request from a downloaded processor (8), transfers the PLD and log files from disk to memory (9), and then the processor loader requests a recovery request (10). In response to the request, information on the log file of the downed processor is requested (11), the information is received, and the log is applied to the PLD in the memory (12). After the application is completed, the processor loader sends a message that the recovery is completed (13) and terminates the database recovery process (14).

According to the present invention configured and operated as described above, the DBMS of the electronic switchgear stores the changed contents of the backup relation in the application program in a log file, and when a backup request is made, the log is applied to the PLD of the disk which is a database copy of the memory. The data is kept consistent and processed to recover to the database state before the downtime when the processor on which the application program was run is down and restarted.

By implementing the method of database backup and recovery with the effect of the present invention in the DBMS of the electronic switchboard, the application always provides the correct data when searching or changing the desired data, even if the processor in which the application was executed goes down. Keeps data in the state it was in before the processor went down, providing the integrity of the data so that applications can continue to run the data they had before the processor went down, accessing unacceptable areas of memory or operating the database. It prevents the enormous damage to the exchange, such as management failure or processor down, so that the exchange maintains high reliability with accurate management of the exchange data at all times.

Claims (1)

OMP (Operation and Maintenance Processor) and data with a Database Management System (DBMS) consisting of three blocks: Data Base Backup Group (DBBG), Data Base Supporting Group (DBSG) and Data Base Kernel Group (DBKG) Database backup and recovery applied to electronic switchboards with many other processors (ASP, INP, MMP) that have only DBSG (Data Base Supporting Group) and DBKG (Data Base Kernel Group) In this method, the application can change the backup relation to receive the changes and apply them to the processor load date (PLD), which is a copy of the database on disk. After performing the first step (1 to 3) of storing the log in a file, and performing the first step (1 to 3), if the data backup request comes, After the logs are taken from the file and the logs are applied to the corresponding PLD on the disk, and the log application is completed, the database backup processing is terminated, and after performing the first steps (1 to 3), the system When the loader receives a restart request from the downed processor, the third step (8 to 10) of transmitting the corresponding PLD and log file from the disk to the memory, and the processor loader requests a recovery request, and the third step (8 to 10). And a fourth step (11 to 14) of receiving the recovery request and receiving information on the log file of the downed processor and applying the log to the PLD in the memory to terminate the recovery process. Database backup and recovery of the DBMS of the electronic switchgear.