[Bug] Mysql Storage Data too long for column 'dest_endpoint'

[kyle-oceanbase]

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• I had searched in the issues and found no similar issues.

Apache SkyWalking Component

OAP server (apache/skywalking)

What happened

I want to know whether skywalking-oap can offer a configuration item to let developers set the max length for each column by ourselves.

I can modify table column with ddl sql, but it seems that skywalking will create new tables by timestamp automatically. I can not modify evey automatically created tables.

2025-07-01 03:43:06,103 org.apache.skywalking.oap.server.storage.plugin.jdbc.common.dao.JDBCBatchDAO 81 [pool-3-thread-1] ERROR [] - [9.7.0-066457b] Data truncation: Data too long for column 'dest_endpoint' at row 1
java.sql.BatchUpdateException: Data truncation: Data too long for column 'dest_endpoint' at row 1
at jdk.internal.reflect.GeneratedConstructorAccessor90.newInstance(Unknown Source) ~[?:?]
at jdk.internal.reflect.DelegatingConstructorAccessorImpl.newInstance(Unknown Source) ~[?:?]
at java.lang.reflect.Constructor.newInstance(Unknown Source) ~[?:?]
at com.mysql.jdbc.Util.handleNewInstance(Util.java:425) ~[mysql-connector-java-5.1.47.jar:5.1.47]
at com.mysql.jdbc.Util.getInstance(Util.java:408) ~[mysql-connector-java-5.1.47.jar:5.1.47]
at com.mysql.jdbc.SQLError.createBatchUpdateException(SQLError.java:1163) ~[mysql-connector-java-5.1.47.jar:5.1.47]
at com.mysql.jdbc.PreparedStatement.executeBatchSerially(PreparedStatement.java:1823) ~[mysql-connector-java-5.1.47.jar:5.1.47]
at com.mysql.jdbc.PreparedStatement.executeBatchInternal(PreparedStatement.java:1307) ~[mysql-connector-java-5.1.47.jar:5.1.47]
at com.mysql.jdbc.StatementImpl.executeBatch(StatementImpl.java:970) ~[mysql-connector-java-5.1.47.jar:5.1.47]
at com.zaxxer.hikari.pool.ProxyStatement.executeBatch(ProxyStatement.java:128) ~[HikariCP-3.1.0.jar:?]
at com.zaxxer.hikari.pool.HikariProxyPreparedStatement.executeBatch(HikariProxyPreparedStatement.java) ~[HikariCP-3.1.0.jar:?]
at org.apache.skywalking.oap.server.storage.plugin.jdbc.BatchSQLExecutor.executeBatch(BatchSQLExecutor.java:85) ~[storage-jdbc-hikaricp-plugin-9.7.0.jar:9.7.0]
at org.apache.skywalking.oap.server.storage.plugin.jdbc.BatchSQLExecutor.invoke(BatchSQLExecutor.java:74) ~[storage-jdbc-hikaricp-plugin-9.7.0.jar:9.7.0]
at org.apache.skywalking.oap.server.storage.plugin.jdbc.common.dao.JDBCBatchDAO.lambda$flush$1(JDBCBatchDAO.java:78) ~[storage-jdbc-hikaricp-plugin-9.7.0.jar:9.7.0]
at java.util.HashMap.forEach(Unknown Source) ~[?:?]
at org.apache.skywalking.oap.server.storage.plugin.jdbc.common.dao.JDBCBatchDAO.flush(JDBCBatchDAO.java:75) ~[storage-jdbc-hikaricp-plugin-9.7.0.jar:9.7.0]
at org.apache.skywalking.oap.server.core.storage.PersistenceTimer.lambda$extractDataAndSave$3(PersistenceTimer.java:135) ~[server-core-9.7.0.jar:9.7.0]
at java.util.concurrent.CompletableFuture$AsyncRun.run(Unknown Source) [?:?]
at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source) [?:?]
at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source) [?:?]
at java.lang.Thread.run(Unknown Source) [?:?]
Caused by: com.mysql.jdbc.MysqlDataTruncation: Data truncation: Data too long for column 'dest_endpoint' at row 1
at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:3976) ~[mysql-connector-java-5.1.47.jar:5.1.47]
at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:3914) ~[mysql-connector-java-5.1.47.jar:5.1.47]
at com.mysql.jdbc.MysqlIO.sendCommand(MysqlIO.java:2530) ~[mysql-connector-java-5.1.47.jar:5.1.47]
at com.mysql.jdbc.MysqlIO.sqlQueryDirect(MysqlIO.java:2683) ~[mysql-connector-java-5.1.47.jar:5.1.47]
at com.mysql.jdbc.ConnectionImpl.execSQL(ConnectionImpl.java:2495) ~[mysql-connector-java-5.1.47.jar:5.1.47]
at com.mysql.jdbc.PreparedStatement.executeInternal(PreparedStatement.java:1903) ~[mysql-connector-java-5.1.47.jar:5.1.47]
at com.mysql.jdbc.PreparedStatement.executeUpdateInternal(PreparedStatement.java:2124) ~[mysql-connector-java-5.1.47.jar:5.1.47]
at com.mysql.jdbc.PreparedStatement.executeBatchSerially(PreparedStatement.java:1801) ~[mysql-connector-java-5.1.47.jar:5.1.47]

What you expected to happen

I want to know whether skywalking-oap can offer a configuration item to let developers set the max length for each column by ourselves.

How to reproduce

just deploy a skywalking oap 9.7.0 and then start java application with skywalking-agent, such errors will happen after a few hours

Anything else

No response

Are you willing to submit a pull request to fix on your own?

• Yes I am willing to submit a pull request on my own!

Code of Conduct

• I agree to follow this project's Code of Conduct

[wu-sheng]

9.7 is not the latest version. We can't verify years ago release.

[kyle-oceanbase]

9.7 is not the latest version. We can't verify years ago release.

Do you mean it has already been fixed int the latest version? Are you sure? Can you show me the commit?

[wu-sheng]

I can't be sure. My team and I are not using MySQL/JDBC storage for the product.
We don't have an update about this. There was a fix for the event table. #12363

[wu-sheng]

My point is, we don't fix for old release, and it has to be something happened in the latest release.

[kyle-oceanbase]

I can't be sure. My team and I are not using MySQL/JDBC storage for the product. We don't have an update about this. There was a fix for the event table. #12363

So the mysql storage implementation is not stable and your team will not support such a storage any more?

[wu-sheng]

This is not my team's work to support that. In ASF, it is the whole community's thing, and driven by volunteers.
My team and I are just users and at the same time maintainers to work on things we are interested in. That is all.

So, I don't know whether it is stable. But people are using it, and as I mentioned above, someone fixed things in 10.1.

Hope you understand the points, and don't treat me as the only one maintaining skywalking.

[wu-sheng]

Features in skywalking are from global contributors/maintainers. I may only use 50% most. So, I am not using doesn't mean for anything about stability and being maintained.

[kyle-oceanbase]

Features in skywalking are from global contributors/maintainers. I may only use 50% most. So, I am not using doesn't mean for anything about stability and being maintained.

I might found the problem, i start skywalking-oap as a k8s deployment with "cluster=standalone"，and i found there's a timer task which will downsampling metrics data.
If i set deployment replicas to 2, there will be two oap pods, i want to know if both of them will run its timer task, thus will cause mysql duplication key error. And how can i solve the problem , can you give me some advice?

[wu-sheng]

If that is the cause, just choose a proper cluster coordinator. You could find the doc in OAP cluster sections.
And if this is the root cause, you will face not just PK conflicts, your data(telemetry) will be overrided(as a kind of dirty write), which cause data inaccurate.

[kyle-oceanbase]

now i have only 1 oap pod，but i can still get error like "Duplicate entry 'instance_client_sidecar_internal_resp_latency_nanos_202507010922_xxx", i have no idea what i can do

[wu-sheng]

I don't have more to comment, as lack of experience.