Why sequence synchronization matters
When you move workloads from on-premise PowerCenter to the IDMC cloud, shared sequences act as the single source of truth for unique identifiers. These reusable sequences allow multiple transformations to pull from the same counter, ensuring consistent primary keys across your data pipelines. However, this convenience introduces a fragile dependency: if the cloud and on-premise instances drift out of sync, your data integrity is immediately compromised.
Manual tracking of sequence values is no longer viable in hybrid environments. As Informatica notes, updating all assets using a sequence generator on the day of a PC cut-off can be highly time-consuming and prone to human error. A single missed update or a manual override can cause the cloud to start generating IDs that already exist in the legacy system, or worse, create gaps that break referential integrity.
Automated synchronization eliminates this guesswork. By ensuring that the cloud and on-premise sequence generators remain aligned, you prevent duplicate key errors and maintain a continuous, gap-free stream of identifiers. This is not just a maintenance task; it is a critical control for data accuracy in any migration or hybrid architecture.
Prepare the sequence generator objects
Before linking PowerCenter to IICS, you must define the Shared Sequence object so both environments recognize it. Informatica documentation describes shared sequences as reusable entities that multiple Sequence Generator transformations can reference. This setup ensures that the sequence values remain consistent across your on-prem and cloud pipelines.
Follow these steps to create and verify the object in the Integration Service and Cloud Data Integration tools.
Open the PowerCenter Designer and navigate to the folder containing your mapping. Right-click the folder and select New > Shared Sequence. Define the starting value, increment, and maximum limit according to your data requirements. This object will serve as the source of truth for your on-prem pipeline.
After defining the sequence, you must publish it to the PowerCenter Integration Service. This step makes the object available to the repository and prepares it for synchronization. Without publishing, the sequence remains local to the Designer session and cannot be accessed by other services or cloud tools.
Log in to the IICS console and open the Cloud Data Integration tool. Navigate to the Shared Objects section and locate the newly published sequence. If the sequence appears, the initial setup is complete. If it is missing, check that the Integration Service name matches the one configured in your IICS connection profile.
Informatica support notes that all assets using the sequence generator must be updated on the day of the PC cut-off. Open your mappings in both PowerCenter and IICS and replace any non-shared sequence references with the new shared object. This ensures that both environments pull from the same value pool during synchronization.
Once verified, your Shared Sequence is ready for synchronization. The next step involves configuring the synchronization settings to ensure values are correctly shared between the two environments.
Synchronize values at the PC cut-off
The cut-off day is the critical migration window where PowerCenter assets must align with Informatica IDMC sequence values. During this phase, the goal is to prevent race conditions by ensuring that legacy workflows and cloud workflows do not generate duplicate keys or skip numbers. This synchronization requires updating all assets that reference the shared sequence generator transformations.
Follow this ordered task sequence to manage the transition:
Before making any changes, halt all active PowerCenter sessions and workflows that rely on the shared sequences. This pause ensures that no new values are generated in the legacy environment while you are adjusting the sequence generator transformations. Confirm that all jobs have stopped and that no background processes are writing to the sequence tables.
Open the PowerCenter Designer and locate every transformation that uses the shared sequences. Update the starting values of these transformations to match the current maximum values stored in the IDMC cloud sequences. This step is time-consuming if you have many assets, so verify each mapping carefully. The objective is to ensure that the next value generated by PowerCenter matches the next value IDMC will generate.
After updating the transformations, validate the sequence generator properties to ensure they reflect the correct starting points. Test a small subset of workflows to confirm that no errors occur and that sequence values are incrementing correctly. Once validated, restart the PowerCenter jobs. Monitor the initial runs closely to ensure that the synchronization holds and that no duplicate keys are introduced.
This process ensures that both environments are aligned before the full migration. Any discrepancy in sequence values can lead to data integrity issues, so precision during this cut-off window is essential.
Validate data integrity post-migration
Synchronization is only as reliable as the data it protects. Before decommissioning legacy assets, you must verify that the new shared sequence generates keys in both environments without overlaps or gaps. This validation step closes the gap between configuration and production safety, ensuring that no duplicate primary keys break downstream loads.
Start by comparing the maximum key values currently held in the sequence generator against the highest key values already inserted into the target tables. If the sequence max is lower than the table max, the next generated key will collide with existing records, causing immediate job failures. Aligning these baselines ensures the sequence starts from a safe, non-conflicting point.
Next, run a sample load in the test environment to confirm that the sequence increments correctly and that the generated keys are unique within the dataset. Check the job logs for any "duplicate key" or "unique constraint" errors. Once the test load succeeds, monitor the production jobs for a short period to confirm stability. If the sequence values drift or repeat, revert to the previous configuration and audit the synchronization logic.
Comparison: Validation Approaches
| Approach | Scope | Risk Level | Primary Outcome |
|---|---|---|---|
| Max Value Comparison | Single sequence, single table | Low | Prevents immediate key collisions |
| Sample Load Test | Multiple tables, full workflow | Medium | Confirms end-to-end key generation |
| Production Monitoring | Live environment, all assets | High | Detects drift and stability issues |
Common synchronization errors and fixes
Even with a solid plan, shared sequence synchronization in Informatica IDMC 2026 can fail due to version mismatches or timing delays during the Production Cut-off (PC). These issues usually stem from incomplete asset updates or race conditions between the Informatica Cloud (IICS) and the underlying database. Below are the most frequent pitfalls and how to resolve them.
1. Missed Sequence Generator Updates
The most common error occurs when not all assets using the sequence generator are updated on the day of the PC cut-off. If even one mapping or procedure relies on the sequence but remains on the older version, it will pull incorrect values, causing gaps or duplicates in your data.
Fix: Before initiating the cut-off, run a dependency check in IICS to identify every asset referencing the shared sequence. Ensure all these assets are updated to the latest version simultaneously. Informatica’s official documentation emphasizes that all dependent assets must be refreshed on cut-off day to maintain consistency [src-serp-1].
2. Database Timeout During Synchronization
When synchronizing large volumes of shared sequences, the database connection may time out before the operation completes. This often happens in high-stakes environments with complex schemas or limited database resources.
Fix: Increase the database connection timeout settings in your IICS connection profile. Additionally, schedule the synchronization during off-peak hours when database load is lower. Monitor the job logs in real-time to catch any partial failures early.
3. Version Mismatch Between IICS and Database
A subtle but critical error is a version mismatch where IICS reports the sequence as synchronized, but the database retains an older state. This can lead to inconsistent sequence generation across different environments.
Fix: Always verify the synchronization status by comparing the sequence values in IICS with the database directly. Use the sequence monitor tool in IICS to confirm that the current and next values align with your target database. If discrepancies exist, re-run the synchronization task for the affected sequences.
Frequently asked questions about shared sequences
Here are specific technical answers regarding synchronization frequency and troubleshooting in Informatica IDMC 2026.
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