Let’s talk about Incremental Table conversion , a topic which is difficult for many people to understand . I have referred this document.
.jpg)
In the ever-evolving realm of database management, upgrading and restructuring tables can be a nerve-wracking experience for businesses. The downtime and operational disruptions often associated with these tasks can create significant challenges. However, there's a silver lining in the form of Incremental (table) Conversion (ICNV). It's an online restructuring method that enables businesses to minimize downtime and smoothly execute the upgrade process. In this blog post, we'll embark on a journey to explore the ICNV, understanding its core concepts and discovering how it can seamlessly integrate with the upgrade tool SUM.
Understanding ICNV in an Upgrade/Update:
Imagine being faced with a critical decision during the crucial PREP_CONFIGURATION/INITSUBST phase of an upgrade. Should you consider ICNV or not? This choice holds the key to efficiency in your upgrade process. Let's explore the two options available:
Do not consider ICNV at all:
This option follows the traditional approach of performing table conversion during downtime. While it's familiar territory, it may not be the most time-effective solution.
Calculate tables for ICNV:
By selecting this option, you open the door to a more innovative path. The ICNVINIT phase in SUM evaluates ICNV candidates and kickstarts successful candidates for further processing. It's like having a knowledgeable advisor by your side, guiding you through the process.
Managing ICNV with SUM: Navigating the Upgrade Journey
Once ICNV candidates have been identified, the SUM upgrade tool steps in, acting as your trusted companion. During the ICNVREQ phase, it prompts you to initiate the transaction ICNV, seamlessly transitioning from evaluation to execution. It's like having a supportive partner who encourages you to take that first step toward a more efficient upgrade.
Key Properties of ICNV:
Minimal Downtime for Table Conversion:
Break and Restart without Loss of Work:
Long-Term Operation
Benefits of ICNV:
The benefits of ICNV extend far beyond the technical realm. Let's explore the advantages it brings:
Reduced Downtime during Upgrades
Simpler Conversion Back to SAP Standard for Modified Tables
Conversion of Large Tables during Production Operation
So Let’s see how it is done
Step 1: Initialization - Setting the Stage for Data Transfer
During the initialization phase, you lay the foundation for the upcoming data transfer process. Follow these steps:
Create the target table(s) for storing the converted data.
This involves defining the new structure and ensuring compatibility with the existing data.
Set up change recording.
Implement a mechanism to track modifications to the original data during the conversion process.
This allows for automatic synchronization of changes made to the original data during the conversion.
Choose 'Control->Initialize'.
This initiates the initialization process and prepares the table for productive conversion.
Step 2: Data Transfer - Migrating Data to the New Structure
The data transfer phase involves moving and converting data from the table with the old structure to the table with the new structure. Follow these steps:
Start the data transfer.
Choose 'Control->Data transfer->Start' to initiate the data transfer process.
The incremental conversion program automatically determines the number and type of background processes required and selects the tables to be processed.
Stop the data transfer (if necessary).
Choose 'Control->Stop everything' to halt the data transfer and terminate running processes.
Use this option when you need to pause the process temporarily or when all processes need to be stopped.
Optimize the data transfer (if needed).
Choose 'Control->Data transfer->Optimize' to evaluate the available background processes on valid servers.
The program determines the number of processes required based on ICNV requirements and schedules additional processes if necessary.
Limit resource requirements (optional).
Set the list of application servers where ICNV processes can execute using 'Edit->Options->Server selection'.
Define the maximum number of background processes allowed for ICNV using 'Edit->Options->Number of processes'.
Define exclusion times (optional).
Use 'Control->Exclusion times' to specify periods during which data transfer should be omitted for individual tables.
This provides further control over resource allocation and allows for prioritization of critical operations.
Step 3: Switch to the New Structure - Activating the Converted Data
The switch phase involves replacing the original table with the target table, making the converted data accessible. Follow these steps:
Lock the original table.
Prevent any further changes to the data in the original table.
Convert remaining data.
Ensure that all data not yet edited by the incremental conversion program is processed and converted.
Replace the virtual original table with the new target table.
Activate the new table definition and make it ready for use.
Reconstruct views based on the original table.
Adjust any views or dependent objects that were based on the original table to reflect the changes made during the conversion.
Step 4: Delete Entry - Finalizing the Conversion
The delete entry phase involves removing the old original data, logs, and locks, allowing modifications to the table in the R/3 Dictionary. Follow these steps:
Remove the table.
Delete the old original data, ensuring it is no longer accessible.
Clear logs and delete locks.
Remove any logs and locks associated with the table to complete the conversion process.
Notes:
1. If the incremental table conversion (ICNV) process has been initiated, it is important to note that conducting an R3LOAD homogeneous or heterogeneous system copy of SAP systems is not supported. Prior to utilizing R3LOAD, it is necessary to complete all ongoing table conversions.
2. The ICNV process employs database-specific methods that cannot be unloaded consistently by R3LOAD. Consequently, there is a potential risk of data loss if attempting to unload ICNV-related data using R3LOAD.
3. It is crucial to verify that no entries are displayed in the transaction ICNV. This ensures that there are no ongoing or pending ICNV processes that may impact system operations or subsequent actions related to table conversions.
Youtube Video to understand in detail
Conversion of tables within the cluster EDI40 is blocked by the tool
336496 - Incremental conversion of cluster tables (may have partial data loss )
1663715 - Selection of additional tables for incremental conversion
807229 - Incremental conversion fails due to activation errors
It is a great website and has a nice article. I want to thank you. Good job! You guys do a great blog, custom erp company in chennai
ReplyDelete