apache/seatunnel · critical · IllegalStateException

The update before event at ${position} for table ${tableId}

Error message

The update before event at ${position} for table ${tableId} was not followed by after event.
 Please report this as a bug together with a events around given LSN.

What it means

An IllegalStateException raised by the SQL Server CDC streaming reader when it dequeues an UPDATE_BEFORE change record but the next record is not the matching UPDATE_AFTER for the same table/LSN. Debezium's contract requires update pairs; breaking it indicates corrupted CDC capture or a reader bug.

Source

Thrown at seatunnel-connectors-v2/connector-cdc/connector-cdc-sqlserver/src/main/java/io/debezium/connector/sqlserver/SqlServerStreamingChangeEventSource.java:428

                                    final TableId tableId =
                                            tableWithSmallestLsn
                                                    .getChangeTable()
                                                    .getSourceTableId();
                                    final int operation = tableWithSmallestLsn.getOperation();
                                    final Object[] data = tableWithSmallestLsn.getData();

                                    // UPDATE consists of two consecutive events, first event
                                    // contains
                                    // the row before it was updated and the second the row after
                                    // it was updated
                                    int eventCount = 1;
                                    if (operation
                                            == SqlServerChangeRecordEmitter.OP_UPDATE_BEFORE) {
                                        if (!tableWithSmallestLsn.next()
                                                || tableWithSmallestLsn.getOperation()
                                                        != SqlServerChangeRecordEmitter
                                                                .OP_UPDATE_AFTER) {
                                            throw new IllegalStateException(
                                                    "The update before event at "
                                                            + tableWithSmallestLsn
                                                                    .getChangePosition()
                                                            + " for table "
                                                            + tableId
                                                            + " was not followed by after event.\n Please report this as a bug together with a events around given LSN.");
                                        }
                                        eventCount = 2;
                                    }
                                    final Object[] dataNext =
                                            (operation
                                                            == SqlServerChangeRecordEmitter
                                                                    .OP_UPDATE_BEFORE)
                                                    ? tableWithSmallestLsn.getData()
                                                    : null;

                                    offsetContext.setChangePosition(
                                            tableWithSmallestLsn.getChangePosition(), eventCount);

View on GitHub (pinned to cf67b549a7)

Solutions

1. Report to SeaTunnel/Debezium with the position and surrounding LSN events as the message instructs
2. Check the SQL Server CDC capture job (sys.cdc jobs) — pause cdc.db_capture cleanup or increase retention
3. Ensure no CDC instance was disabled/altered for the table during streaming
4. Re-snapshot the affected table (restart job from snapshot) to restore a consistent stream
5. Upgrade to the latest Debezium/SeaTunnel CDC version where pairing bugs may be fixed

-- before streaming, ensure capture jobs are healthy and retention is sufficient
SELECT name, retention, pollinterval FROM msdb.dbo.cdc_jobs;

catch (IllegalStateException e) {
    if (e.getMessage().contains("was not followed by after event")) {
        LOG.error("CDC update-pair invariant broken; resnapshot the table", e);
        // restart job from snapshot
    }
    throw e;
}

When it happens

Trigger: During streamedEvent iteration: the merge-heap (tableWithSmallestLsn) returns OP_UPDATE_BEFORE whose next entry differs in operation or table, typically because CDC capture tables were partially cleaned or an LSN was skipped while polling.

Common situations: sys.cdc cleanup job removing rows between the before/after reads; concurrent capture-instance changes (disable/enable CDC) while streaming; reading across an AG failover; a genuine Debezium bug — the message asks you to report it with surrounding LSN events.

Understand the failure class

Background: "This is a bug, please report it": internal invariant violations, unreachable panics, and SNH errors explained — this error's family across 47 libraries.

Related errors

• The table changes should only have one element
• Unable to instantiate the database history class " + config.
• Data change record shouldn't use READ operation, the the rec
• Unknown table change type:
• should not call here, error

AI-assisted analysis of apache/seatunnel@cf67b549a7 (2026-09-10). Data as JSON: /api/errors/31dc70b1b64c1b0f. Report an issue: GitHub.