SAP HANA – Data Replication through SLT
This document presents step by step procedure for Trigger-Based Data Replication from ECC to HANA system using SAP Landscape Transformation (SLT) based on capturing database changes at a high level of abstraction in the source ERP system.
Initial Load and Simultaneous Delta Replication
The initial load of business data is initiated using the SAP HANA studio. The initial load message is sent from the SAP HANA system to the SLT system (based on SAP NetWeaver 7.02 with kernel 7.20 EXT), which in turn passes the initialization message to the ERP system. The ERP system begins by setting up database transaction log tables for each table to be replicated. After the transaction tables are completed, the SLT system begins a multi-threaded replication of data to the target system, which enables high speed data transfer.
The initial load of data can be executed while the source system is active. The system load that this process causes can be controlled by adjusting the number of worker threads performing the initial replication.
In parallel to the initial load, by means of database-specific triggers, the SLT system begins detecting any data changes that occur while the initial load process is running. These changes are logged to the transaction tables, and are propagated to the target SAP HANA system.
Continuous Delta Replication after Initial Load
After the initial load process has completed, the SLT system continues to monitor the transaction tables in the ERP system, and replicates data changes in the source system to the SAP HANA system in near real time.
Step by Step Procedure for Replication:
Enter a distinct configuration name (A schema of same name would be created in HANA system), Initial load mode as resource optimized, appropriate RFC Connection (ECC <–> LT), Data Transfer and calculation jobs. Replication would be Real time. Also mention the target HANA system credentials and click on Ok.
2. Logon to HANA Studio with the appropriate credentials . Here a schema of same name as configuration would be created.
Click on Data Provisioning through Quick Launch.
This will take take us to SLT Based Table Data Provisioning. Here we can see 3 tables are already being replicated without user replicating them. These tables basically provide HANA system with information of all the tables in source system.
Now for loading any table click on “Load” and select the table from the list of tables available in the source system and click finish.
Lets first take an example of loading Material master table – MARA
The loading is scheduled and once completed status is set as executed.
With this, table “MARA” get loaded from Source ECC system to SAP HANA system.
For replication purpose lets take example of application table –VBAP (Sales Document line item data).
Click on “Replication” button and select VBAP table.
This will load the VBAP table and then set the status “In process” for replicating changes in the VBAP table in source system.
To show the replication process lets create one more record on the ECC side (with reference) which gets replicated to the HANA system as shown below:
Now a Sales Document with Document number (VBELN) – 13553 is created.
The same document would be replicated to HANA system in real time.
This completes our basic objective of replicating data from SAP ECC system to SAP HANA system in real time using SLT.
Thanks for sharing knowledge. Really useful for beginners
Hi, thanks for the detailed blog on SLT.
So i understand that even if the table is not loaded for the first time, and if user clicks on " replicate" button in the studio, it will still trigger the first load and replicate later.
One question is : is the size of the Log table defined / configurable anywhere?
Thanks Ranjit , Aruna and Sudha..
@Sudha :We can set the maximum allowed value (maximum number of result record) using preferences but as far as size of log tables is concerned I think HANA Admin takes care of it ...as an application developer we refer job logs to find successful/unsuccessful jobs and its cause. I will revert back to you once i find an appropriate answer to your question..
Absolutely Useful for the beginners who have been hearing about SAP LT server but been not able to see the system in real!! Good one Ankit!
Thanks Ankit! Provides a clear understanding on SLT and its purpose.
First of all, thanks a lot of this step by step guide.
I have a question to complete the sales order process described above.
Assume we replicate the good issue table and post the good issue in the source system. Good issue document will be then replicated to Hana.
Is there any way to automatically generate the financial posting in Hana based on its configuration based on the good issue document?
That's detailed information, Thanks for providing that. I believe there should a table which holds all the table load details and its time stamp. Could you let me know if any one aware of this table.
For those who found the blog, the main transaction is "LTR". It is unclear from the screenshots.
Thanks for sharing.
Can we use SLT to replicate data from SalesForce? if so what adaptor needs to be used?