What is Watermark Synchronisation?

Watermark synchronisation tracks the last processed point in a data sync workflow. Learn how SQL Server teams use watermarks and how SQL Cockpit relates.

See SQL Cockpit plans Book a demo

Definition

Watermark synchronisation uses a stored checkpoint, such as a timestamp, identity value, rowversion, sequence, or custom marker, to identify which records have already been processed.

Why it matters

Watermarks make recurring synchronisation more efficient.
They help teams resume after failures without guessing what was processed.
Poorly managed watermarks can cause missed or duplicate records.

Common signals

A sync job processes only rows changed since the previous run.
A migration process keeps a last-successful timestamp or ID.
A failed batch must resume without reprocessing the full source table.

How SQL Cockpit helps

SQL Cockpit ties synchronisation work to visible operational context so checkpoints, status, validation, and follow-up actions can be reviewed.
Watermark-based sync decisions can be discussed alongside table context, migration progress, and job monitoring.

FAQ

What can be used as a synchronisation watermark?

Common watermarks include modified timestamps, identity columns, sequence values, SQL Server rowversion values, or custom checkpoint records.

What happens if a watermark is wrong?

An incorrect watermark can skip records, duplicate records, or make validation harder because the sync process no longer has a reliable checkpoint.

How does SQL Cockpit relate to watermark synchronisation?

SQL Cockpit gives teams a visible workflow around synchronisation, job status, table context, and validation.