@Override
    protected SnapshotResult doExecute(
            ChangeEventSourceContext context,
            SnapshotContext snapshotContext,
            SnapshottingTask snapshottingTask)
            throws Exception {
        final RelationalSnapshotChangeEventSource.RelationalSnapshotContext ctx =
                (RelationalSnapshotChangeEventSource.RelationalSnapshotContext) snapshotContext;
        ctx.offset = offsetContext;
        final SignalEventDispatcher signalEventDispatcher =
                new SignalEventDispatcher(
                        offsetContext.getPartition(),
                        topicSelector.topicNameFor(snapshotSplit.getTableId()),
                        dispatcher.getQueue());

        final BinlogOffset lowWatermark = currentBinlogOffset(jdbcConnection);
        LOG.info(
                "Snapshot step 1 - Determining low watermark {} for split {}",
                lowWatermark,
                snapshotSplit);
        ((SnapshotSplitReader.SnapshotSplitChangeEventSourceContextImpl) (context))
                .setLowWatermark(lowWatermark);
        signalEventDispatcher.dispatchWatermarkEvent(
                snapshotSplit, lowWatermark, SignalEventDispatcher.WatermarkKind.LOW);

        LOG.info("Snapshot step 2 - Snapshotting data");
        createDataEvents(ctx, snapshotSplit.getTableId());

        BinlogOffset highWatermark = determineHighWatermark(lowWatermark);

        LOG.info(
                "Snapshot step 3 - Determining high watermark {} for split {}",
                highWatermark,
                snapshotSplit);
        signalEventDispatcher.dispatchWatermarkEvent(
                snapshotSplit, highWatermark, SignalEventDispatcher.WatermarkKind.HIGH);
        ((SnapshotSplitReader.SnapshotSplitChangeEventSourceContextImpl) (context))
                .setHighWatermark(highWatermark);

        Table table = databaseSchema.tableFor(snapshotSplit.getTableId());
        if (table == null) {
            return SnapshotResult.skipped(ctx.offset);
        }

        return SnapshotResult.completed(ctx.offset);
    }
Interval for showing a log statement with the progress while scanning a single table.
inlong-sort/sort-flink/sort-flink-v1.13/sort-connectors/mysql-cdc/src/main/java/org/apache/inlong/sort/cdc/mysql/debezium/task/MySqlSnapshotSplitReadTask.java