Turn: Oracle goldengate Learning goldengate Introduction

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Log or archive log to obtain data additions and deletions change, and then apply these changes to the target database, the source database and the target database synchronization, dual-live. GoldenGate TDM Software enables a large amount of data sub-second real-time replication between heterogeneous IT infrastructures, including almost all common operating system platforms and database platforms, with a simplified copy of the following:

goldengate TDM The data copy process is as follows:

using the capture process to read online Redo log or archive log on the source system, and then parse, only extract the changes in the data such as add, delete, change operation, and convert the relevant information to Goldengate TDM custom intermediate format is stored in the queue file. The transfer process is then used to transfer the queue file over TCP/IP to the target system. The capture process, after each reading of the data in log and after the data is transferred to the target system, writes a checkpoint, records the log position of the current completed capture, and the presence of the checkpoint allows the capture process to continue copying from the checkpoint location after it is aborted and resumed;

The target system accepts data changes and caches them into the Goldengate TDM queue, which is a series of files that temporarily store data changes, waiting for the delivery process to read the data;

The GoldenGate TDM delivery process reads data changes from the queue and creates corresponding SQL statements, executes through the database's local interface, submits to the database successfully, updates its checkpoint, logs the location where replication has completed, The replication process for the data is eventually completed.

Thus, GoldenGate TDM is a software-based approach to data replication that parses data from the database's logs (data volumes are only about One-fourth of the log ). GoldenGate TDM transforms data into its own format, directly over a TCP/IP network, without relying on the way the database itself is delivered, and by compressing data by up to 9:1, which can significantly reduce bandwidth requirements. On the target side, GoldenGate TDM can greatly accelerate the speed and efficiency of data delivery, reduce the resource consumption of target system, and realize the replication of large amounts of data at sub-second level by means of trade recombination, batch loading and other technologies, and the target database is active

GoldenGate TDM provides a flexible application solution based on its advanced, flexible technology architecture that can compose a variety of topologies based on user requirements:

GoldenGate TDM provides reliable data replication, mainly in the following three points:

Ensure transactional consistency

GoldenGate TDM Application Replication database transactions in the disaster recovery database are in the same order as in the production Center database and submitted in the same transactional environment, ensuring the integrity and read consistency of the data on the target system, creating conditions for real-time query and transaction processing.

Checkpoint mechanism ensures no loss of data.

The GoldenGate TDM extraction and replication process uses a checkpoint mechanism to record where the replication has completed. For the extraction process, its checkpoint records the location of the currently extracted log and the location of the write queue file, and for the delivery process, its checkpoint records the location of the current read queue file. The checkpoint mechanism ensures that no data is lost after a system, network, or goldengate TDM process failure restart.

Reliable data transfer mechanism

GoldenGate TDM transmits transaction data using a response mechanism, the data is not considered complete until the confirmation message is received, otherwise it is automatically retransmitted, guaranteeing that all the extracted data can be sent to the backup side. 128-bit encryption and data compression are supported during data transfer.

GoldenGate TDM provides reliable data replication, mainly in the following three points:

Ensure transactional consistency

GoldenGate TDM Application Replication database transactions in the disaster recovery database are in the same order as in the production Center database and submitted in the same transactional environment, ensuring the integrity and read consistency of the data on the target system, creating conditions for real-time query and transaction processing.

Checkpoint mechanism ensures no loss of data.

The GoldenGate TDM extraction and replication process uses a checkpoint mechanism to record where the replication has completed. For the extraction process, its checkpoint records the location of the currently extracted log and the location of the write queue file, and for the delivery process, its checkpoint records the location of the current read queue file. The checkpoint mechanism ensures that no data is lost after a system, network, or goldengate TDM process failure restart.

Reliable data transfer mechanism

GoldenGate TDM transmits transaction data using a response mechanism, the data is not considered complete until the confirmation message is received, otherwise it is automatically retransmitted, guaranteeing that all the extracted data can be sent to the backup side. 128-bit encryption and data compression are supported during data transfer.

Oracle's Goldengate products enable data capture, transformation, and delivery of large amounts of data across heterogeneous IT infrastructures. Goldengate can support almost all common operating systems such as and database platforms, as shown in the following table:

Operating system	Database
MS NT, +, XP, Linux, Sun Solaris, HP-UX, IBM AIX, HP NonStop, TRU64, IBM z/os,os/390	Oracle, DB2, MS SQL Server, MySQL, Enscribe, SQL/MP, Sql/mx, Sybase, Teradata, other ODBC-compatible databases