Question

在使用多文档交易时，我遇到很多麻烦。其中之一恰好是-每当[同一个事务中]同一文档上有多个更新时，Mongo都会抛出一个奇怪的错误“ com.mongodb.MongoCommandException: Command failed with error 251 (NoSuchTransaction): 'Transaction 1 has been aborted.' on server .....”。我朝着可见的方向看了它，并调整了诸如“

”这样的读写问题的选项

WriteConcern.MAJORITY，ReadPreference.PRIMARY，ReadConcern.SNAPSHOT。

我正在使用Java驱动程序，并且交易开始的代码段如下所示

TransactionOptions transactionOptions = TransactionOptions.builder()
.writeConcern(WriteConcern.MAJORITY)
.readPreference(ReadPreference.primary())
.readConcern(ReadConcern.SNAPSHOT)
.build();

ClientSessionOptions clientSessionOptions = ClientSessionOptions
.builder()
.defaultTransactionOptions(transactionOptions)
.build();

this.session = mongo.startSession(clientSessionOptions);
this.session.startTransaction(transactionOptions);

有人对此错误有想法吗？

Answer 1

为了获得有关该错误的更多上下文，您需要检查Mongodb的日志。

在Mongo shell mongo中，运行show log global，您将看到事务失败的原因。

就我而言，由于以下原因而失败：

[startPeriodicThreadToAbortExpiredTransactions] Aborting transaction with 
txnNumber 1 on session ea5e8c8d-ecc2-47ca-8901-55a43143a809 because it has 
been running for longer than 'transactionLifetimeLimitSeconds'

这看起来像是MongoDB中的错误，因为它应该引发transactionLifetimeLimitSeconds错误，或者至少告诉您是什么问题。

Answer 2

该事务可能包括修改数据库目录的操作。由于在不存在的集合上执行insert操作，导致遇到相同的错误。提交事务时发生251错误。

my-rs:PRIMARY> use mytest
switched to db mytest
my-rs:PRIMARY> show collections
my-rs:PRIMARY> session.startTransaction()
my-rs:PRIMARY> session.getDatabase('mytest').newcollection.insert({"a":"b"});
WriteCommandError({
    "operationTime" : Timestamp(1554822412, 1),
    "ok" : 0,
    "errmsg" : "Cannot create namespace mytest.newcollection in multi-document transaction.",
    "code" : 263,
    "codeName" : "OperationNotSupportedInTransaction",
    "$clusterTime" : {
        "clusterTime" : Timestamp(1554822412, 1),
        "signature" : {
            "hash" : BinData(0,"AAAAAAAAAAAAAAAAAAAAAAAAAAA="),
            "keyId" : NumberLong(0)
        }
    }
})
my-rs:PRIMARY> session.commitTransaction()
2019-04-09T15:07:04.695+0000 E QUERY    [js] Error: command failed: {
    "errorLabels" : [
        "TransientTransactionError"
    ],
    "operationTime" : Timestamp(1554822422, 1),
    "ok" : 0,
    "errmsg" : "Transaction 8 has been aborted.",
    "code" : 251,
    "codeName" : "NoSuchTransaction",
    "$clusterTime" : {
        "clusterTime" : Timestamp(1554822422, 1),
        "signature" : {
            "hash" : BinData(0,"AAAAAAAAAAAAAAAAAAAAAAAAAAA="),
            "keyId" : NumberLong(0)
        }
    }
} :
_getErrorWithCode@src/mongo/shell/utils.js:25:13
doassert@src/mongo/shell/assert.js:18:14
_assertCommandWorked@src/mongo/shell/assert.js:536:17
assert.commandWorked@src/mongo/shell/assert.js:620:16
commitTransaction@src/mongo/shell/session.js:942:17
@(shell):1:1
my-rs:PRIMARY>

请参阅https://docs.mongodb.com/manual/core/transactions/#restricted-operations

MongoDB的多文档事务中的同一文档的多个更新问题

2 个答案: