Hi all, I have reported this bug on the github, and I would like to discuss this issue with you guys. Please take a look my report.
This is test code and patch https://github.com/h2database/h2database/pull/500 Test Version: 1.4.194Precondition: 1. Test databse CREATE TABLE test ( entity_id INTEGER NOT NULL PRIMARY KEY, lastUpdated INTEGER NOT NULL) INSERT INTO test (entity_id, lastUpdated) VALUES (1, 100) 1. DB URL jdbc:h2:mem:qed;DB_CLOSE_DELAY=-1;MVCC=TRUE;LOCK_TIMEOUT=120000;MULTI_THREADED=TRUE") Reproduction scenario: Launch multiple threads which are executing query "select for update" in a infinite loop. SELECT * FROM test WHERE entity_id = 1 FOR UPDATE Problem: row with "entity_id = 1" disappeard Cause: When a thread commits its transaction, a row with null value is remove. problem is that if the transaction id of the row with null value is not same as current committing transaction id, the row should be preserved. Relative code // src/main/org/h2/mvstore/db/TransactionStore.java void commit(Transaction t, long maxLogId) { } else if (value.value == null) { // remove the value map.remove(key); } My Suggestion Remove a row with null value only if its transaction id is same as current one // src/main/org/h2/mvstore/db/TransactionStore.java void commit(Transaction t, long maxLogId) { } else if (value.value == null) { int tx = getTransactionId(value.operationId); if (tx == t.transactionId) { // remove the value only if it's transaction id is same as current transaction id map.remove(key); } } ## Relative Issue I found this is when I debugging the issue #180 <https://github.com/h2database/h2database/issues/180> -- You received this message because you are subscribed to the Google Groups "H2 Database" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To post to this group, send email to [email protected]. Visit this group at https://groups.google.com/group/h2-database. For more options, visit https://groups.google.com/d/optout.
