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【DM版本】: 8.4安全版
【操作系统】：KylinV10SP3
【CPU】:海光
【问题描述】*：
执行嵌套事务的时候报错：
2026-03-26 20:10:10:07 [ShardingSphere-Command-5] WARN c.zaxxer.hikari.pool.ProxyConnection - HikariPool-5 - Connection dm.jdbc.driver:DmdbConnection@47550111 marked as broken because of SQLSTATE(08003), ErrorCode(6003)
dm.jdbc.driver.DMException: 连接尚未建立或已经关闭
at dm.jdbc.driver.DBError.throwException(DBError.java:700)
at dm.jdbc.driver.DmdbResultSet.checkConnection(DmdbResultSet.java:1998)
at dm.jdbc.driver.DmdbResultSet.next(DmdbResultSet.java:2066)
at com.zaxxer.hikari.pool.HikariProxyResultSet.next(HikariProxyResultSet.java:635)
at org.apache.shardingsphere.infra.executor.sql.execute.result.query.impl.driver.jdbc.type.stream.JDBCStreamQueryResult.next(JDBCStreamQueryResult.java:54)
at org.apache.shardingsphere.infra.executor.sql.execute.result.query.impl.transparent.TransparentMergedResult.next(TransparentMergedResult.java:39)
at org.apache.shardingsphere.proxy.backend.communication.DatabaseConnector.next(DatabaseConnector.java:353)
at org.apache.shardingsphere.proxy.frontend.postgresql.command.query.extended.Portal.hasNext(Portal.java:209)
at org.apache.shardingsphere.proxy.frontend.postgresql.command.query.extended.Portal$1.hasNext(Portal.java:166)
at org.apache.shardingsphere.proxy.frontend.postgresql.command.query.extended.PostgreSQLAggregatedCommandExecutor.advance(PostgreSQLAggregatedCommandExecutor.java:81)
at org.apache.shardingsphere.proxy.frontend.postgresql.command.query.extended.PostgreSQLAggregatedCommandExecutor$1.hasNext(PostgreSQLAggregatedCommandExecutor.java:49)
at org.apache.shardingsphere.proxy.frontend.command.CommandExecutorTask.doExecuteCommand(CommandExecutorTask.java:154)
at org.apache.shardingsphere.proxy.frontend.command.CommandExecutorTask.executeCommand(CommandExecutorTask.java:93)
at org.apache.shardingsphere.proxy.frontend.command.CommandExecutorTask.run(CommandExecutorTask.java:138)
at com.alibaba.ttl.TtlRunnable.run(TtlRunnable.java:60)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:635)
at java.lang.Thread.run(Thread.java:833)