apache/seatunnel · error · DebeziumException

Failed to resolve snapshot offset

Error message

Failed to resolve snapshot offset

What it means

getPendingTransactionsFromLogs starts a LogMiner session to mine redo logs for transactions that were in-flight during the snapshot, so their start SCNs can be recorded in the offset. Any exception thrown during this log-mining pass (JDBC errors, LogMiner session failures, query errors) is wrapped in this DebeziumException, and the caller determineSnapshotOffset then fails the snapshot.

Source

Thrown at seatunnel-connectors-v2/connector-cdc/connector-cdc-oracle/src/main/java/io/debezium/connector/oracle/logminer/LogMinerAdapter.java:389

                        rs -> {
                            while (rs.next()) {
                                final String transactionId =
                                        HexConverter.convertToHexString(rs.getBytes("XID"));
                                final String startScnStr = rs.getString("START_SCN");
                                if (!Strings.isNullOrBlank(startScnStr)) {
                                    final Scn startScn = Scn.valueOf(rs.getString("START_SCN"));
                                    if (!pendingTransactions.containsKey(transactionId)) {
                                        LOGGER.info(
                                                "\tTransaction '{}' started at SCN '{}'",
                                                transactionId,
                                                startScn);
                                        pendingTransactions.put(transactionId, startScn);
                                    }
                                }
                            }
                        });
            } catch (Exception e) {
                throw new DebeziumException("Failed to resolve snapshot offset", e);
            } finally {
                stopSession(connection);
            }
        }
    }

    private List<LogFile> getMostRecentLogFilesForSearch(List<LogFile> allLogFiles) {
        Map<Integer, List<LogFile>> recentLogsPerThread = new HashMap<>();
        for (LogFile logFile : allLogFiles) {
            if (!recentLogsPerThread.containsKey(logFile.getThread())) {
                if (logFile.isCurrent()) {
                    recentLogsPerThread.put(logFile.getThread(), new ArrayList<>());
                    recentLogsPerThread.get(logFile.getThread()).add(logFile);
                    final Optional<LogFile> maxArchiveLogFile =
                            allLogFiles.stream()
                                    .filter(
                                            f ->
                                                    logFile.getThread() == f.getThread()

View on GitHub (pinned to cf67b549a7)

Solutions

1. Read the wrapped cause for the specific ORA- error and fix accordingly (e.g. restore/pin archive logs for the mining window)
2. Grant the connector user LogMiner-related privileges and access to the log mining dictionary
3. Ensure archive logs covering the snapshot SCN range are retained (increase RMAN retention / avoid deleting active logs)
4. Re-run the snapshot after fixing log retention or privilege issues

-- Ensure archive logs covering the snapshot window are retained:
SELECT NAME, FIRST_CHANGE#, NEXT_CHANGE#, DELETED FROM V$ARCHIVED_LOG ORDER BY FIRST_CHANGE#;
-- RMAN: CONFIGURE RETENTION POLICY ... ; do not delete logs still needed

try {
    adapter.determineSnapshotOffset(...);
} catch (DebeziumException e) {
    if (e.getMessage().startsWith("Failed to resolve snapshot offset") && e.getCause() != null) {
        logOraError(e.getCause()); // inspect ORA- code, fix retention/privileges, then retry snapshot
    } else { throw e; }
}

When it happens

Trigger: determineSnapshotOffset -> getPendingTransactionsFromLogs executes the LogMiner mining loop over v$logmnr_contents; the underlying query/session throws (invalid STARTSCN, missing archive logs, ORA- errors from LogMiner, insufficient privileges).

Common situations: Required redo/archive logs already purged so the mining window is invalid; LogMiner session start fails due to permissions or dictionary issues; long-running snapshot transactions exceed retained logs; Oracle raises ORA-01291 (missing logfile).

Understand the failure class

Background: "query failed", "%w: SQL error" — wrapped database query errors in Go libraries explained — this error's family across 3 libraries.

Related errors

• Failed to resolve current SCN
• Online REDO LOG files or archive log files do not contain th
• Failed to calculate oldest SCN available in logs
• Cannot get maximum archive log SCN as no logs were available
• Cannot get maximum archive log SCN as no archive logs are pr

AI-assisted analysis of apache/seatunnel@cf67b549a7 (2026-09-10). Data as JSON: /api/errors/f74e84d4daf89a71. Report an issue: GitHub.