Details
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Bug
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Resolution: Done
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Critical
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0.9.3.Final
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None
Description
I use debezium connector to extract data from oracle 11g/12c.
I found the topic is missing a lot of messages then i wrote a little test code. Below is the code
String insertCustomer = "INSERT INTO CUSTOMER (ID , FULLNAME) VALUES(?, ?)"; try { Class.forName("oracle.jdbc.driver.OracleDriver"); //11g //Connection connection = DriverManager.getConnection("jdbc:oracle:thin:@10.177.83.9:1521:ycdb", "dmdata", "dmdata"); //12c Connection connection = DriverManager.getConnection("jdbc:oracle:thin:@10.7.112.18:1521/dmpdb", "debezium", "dbz"); connection.setAutoCommit(false); for (int i =1 ; i< 5 ; i++) { PreparedStatement ps = connection.prepareStatement(insertCustomer); ps.setInt(1 , i); ps.setString(2 , "helloworld" + i); ps.executeUpdate(); } connection.commit(); connection.close(); } catch (SQLException e) { System.out.println("Connection Failed! Check output console"); e.printStackTrace(); return; } catch (ClassNotFoundException e) { e.printStackTrace(); return; }
Basically the code is turned off the auto commit and use jdbc transaction, so what happened is "insert multiple rows , then do a single commit " i can only see ONE message is produced to the topic
Then i try to debug the code what i found the code below in oracle-connector
"LcrEventHandler.java , line 56 "
// After a restart it may happen we get the event with the last processed SCN again if (scn <= offsetContext.getScn()) { LOGGER.debug("Ignoring change event with already processed SCN {}", scn); return; }
what happens in oracle multiple DML in one transaction share same scn , so when this handler processed a LCR, if next LCR have same scn it will just return.
I don't fully understand the logic , this is all information i know.
Thanks for the help
