What is Qlik Replicate?
Qlik Replicate is a simple, powerful, easy-to-implement solution that provides replication between various endpoints.
Replicate lets you:
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Load data efficiently and quickly to operational data stores/warehouses
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Create copies of production endpoints
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Distribute data across endpoints
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Replicate is designed to scale and support large scale enterprise data replication scenarios with a scalable multi-server, multi-task, and multi-threaded architecture.
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Replicate consists of a Web-based console and a replication server to replicate data across both heterogeneous and homogeneous data sources. It provides users with instant visibility into current and historical tasks, status, performance, and resource usage information.
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Replicate can execute replication tasks between a large number of enterprise endpoints including Oracle, Microsoft SQL Server, and IBM DB2. It uses a "Click-2-Replicate" design that simplifies the replication process by automating the steps required to build a replication solution.
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When you set up a task in Replicate, you can select any of the following:
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Full Load Replication: Creates files or tables on the target endpoint, automatically defines the metadata that is required on the target, and populates the tables with data from the source
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Change Processing, also called Change Data Capture (CDC): Captures changes in the source data or metadata as they occur and applies them to the target endpoint as soon as possible, in near-real time
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Store Changes: Captures changes in the source data or metadata as they occur but does not apply them to the target
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Replication is log based, which means that it reads only the changes. This reduces the impact on the source endpoints.
System Architecture
In the initial load process, Qlik Replicate reads a filtered stream of rows (with relevant columns only) and passes them to the transformation process for further filtering and subsequent writing to the target endpoint (in the expected output format).
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The CDC process obtains a stream of filtered events or changes in data or metadata from the transaction log file. It then buffers all changes for a given transaction into a single unit before forwarding them to the target when the transaction is committed. During the initial load process, CDC also buffers all changes that occur within a transaction until all affected tables have been loaded.
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This diagram shows the basic architecture of Qlik Replicate.
