Database integration starts with the source’s operating constraints: which records may be read, how changes are represented, how much extraction load is acceptable and how the analytical copy will recover after interruption.
This guide compares common integration patterns for partnership and architecture discussions. PostgreSQL appears as an educational reference for logical replication. The patterns do not constitute a list of currently available Covorg connectors or prescribe a specific database technology.
Choose a capture pattern that fits the source
A complete snapshot is straightforward to reconcile but can become expensive as data grows. Incremental extraction reduces repeated reads when the source provides a dependable change marker. Change data capture can represent ongoing inserts, updates and deletions, but introduces source configuration and recovery responsibilities.
| Pattern | Appropriate starting point | Principal design question |
|---|---|---|
| Snapshot | Small datasets or periodic reference data | Can the extract represent a consistent source state? |
| Incremental query | Reliable modification marker and stable identity | How are ties, deletions and corrections captured? |
| Change data capture | Frequent changes with suitable source support | How are snapshots, log positions and replay coordinated? |
| Published view | A source owner provides a defined data contract | Who manages schema changes and completeness? |
Make incremental boundaries deterministic
A modification timestamp alone may not be a unique cursor. Several records can share the same value, and updates can occur while pages are being read. Define a stable ordering and an extraction boundary that the source can support, then preserve the checkpoint only after accepted output is recoverable.
An overlap window with deduplication can help with delayed updates, but it does not solve every source behaviour. Hard deletions may disappear before a query sees them, and a field that is not updated reliably cannot serve as a dependable change marker. Document these limits during discovery.
Coordinate initial state and ongoing changes
PostgreSQL describes logical replication as a publication and subscription model that typically begins with an initial table snapshot and then applies subsequent changes. Replication identity, usually a primary key, helps identify the affected records. Record identity and snapshot boundaries are therefore central to a change capture design.
The analytical destination also needs an update rule. A latest state table applies changes to a stable record identity, while a historical model may retain successive versions. Neither form should be selected by accident; they answer different business questions and require different storage and retention decisions.
Evaluate source protection and recovery
Use an account limited to the required resources and operations, with approved network access and secret handling. Review extraction schedules and query plans with the source owner where load could affect business transactions. A convenient analytical query should not become an unexamined operational dependency.
Monitor source freshness, extraction progress, backlog and reconciliation results. If a consumer falls behind beyond available change history, a new snapshot may be required. Define that recovery process, including how downstream views will be marked while the analytical state is rebuilt.
Database integration assessment
- 01
Discover
Identify source ownership, permissions, identities and update behaviour.
- 02
Select
Compare capture patterns against freshness and source load requirements.
- 03
Validate
Reconcile an initial extract and exercise update and deletion scenarios.
- 04
Recover
Verify restart boundaries, duplicate handling and rebuild procedures.
Design considerations
- Confirm how deletions and historical corrections become visible to the integration.
- Agree source load limits and extraction permissions with the database owner.
- Treat a change in source schema as a contract review, not an automatic analytical change.
Sources
The following sources explain the underlying technical patterns.
