ddl操作导致pipleline一直报错

进行ddl操作,加了一个索引
ALTER TABLE `a`.`b`
ADD INDEX `c` (`d` ASC);
就一直报错:
pid:6 nid:1 exception:setl:com.alibaba.otter.node.etl.select.exceptions.SelectException: java.lang.NullPointerException
at com.alibaba.otter.node.etl.select.selector.MessageParser.parse(MessageParser.java:211)
at com.alibaba.otter.node.etl.select.selector.canal.CanalEmbedSelector.selector(CanalEmbedSelector.java:308)
at com.alibaba.otter.node.etl.select.SelectTask.processSelect(SelectTask.java:236)
at com.alibaba.otter.node.etl.select.SelectTask.access$300(SelectTask.java:94)
at com.alibaba.otter.node.etl.select.SelectTask$1.run(SelectTask.java:208)
at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511)
at java.util.concurrent.FutureTask.run(FutureTask.java:266)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
at java.lang.Thread.run(Thread.java:748)
Caused by: java.lang.NullPointerException
at com.alibaba.otter.node.etl.select.selector.MessageParser.internParse(MessageParser.java:380)
at com.alibaba.otter.node.etl.select.selector.MessageParser.parse(MessageParser.java:183)
... 9 more

Reproduce the reported ALTER TABLE ... ADD INDEX operation and inspect MessageParser.java at lines 211 and 380, where the NullPointerException is reported. Trace how CanalEmbedSelector.java line 308 passes the DDL event into MessageParser. Done means the pipeline no longer fails with this DDL operation.

Written by the indexing model from the issue text.