Duplicate Keys in Oracle Berkeley DB Java Edition

Question

I'm using Oracle Berkeley DB Java Edition with tables having key/value format. I'm trying to insert duplicate keys, but keep getting SecondaryIntegrityException. According to Oracle, if the setSortedDuplicates() is set to true, then duplicates are allowed. This does not work in my case. Below is some code with key=bob, value=smith. The first I run it, it runs as expected. If I run it a second time changing only value=johnson, I get SecondaryIntegrityException. Is there something I'm doing wrong? Thanks.

String key = "bob";
String value = "smith";

EnvironmentConfig envConfig = new EnvironmentConfig();
envConfig.setAllowCreate(true);
envConfig.setTransactional(false);
Environment myDBenvironment = new Environment(new File(filePath), envConfig);


DatabaseConfig dbConfig = new DatabaseConfig();
dbConfig.setAllowCreate(true);
dbConfig.setTransactional(false);
Database myDatabase = myDBenvironment.openDatabase(null, dbname,
        dbConfig);

// create secondary database
SecondaryConfig mySecConfig = new SecondaryConfig();
mySecConfig.setAllowCreate(true);
mySecConfig.setSortedDuplicates(true);
mySecConfig.setTransactional(false);
mySecConfig.setKeyCreator(new SecondKeyCreator());
SecondaryDatabase mySecondaryDatabase = myDBenvironment
.openSecondaryDatabase(null, secdbname, myDatabase,
        mySecConfig);


DatabaseEntry myKey = new DatabaseEntry(key.getBytes("UTF-8"));

Record mydata = new Record();
mydata.setobjectVal(value);
DatabaseEntry myrecord = new DatabaseEntry();
new RecordTupleBinding().objectToEntry(mydata, myrecord);
myDatabase.put(null, myKey, myrecord);

mySecondaryDatabase.close();
myDatabase.close();
myDBenvironment.close();


public class SecondKeyCreator implements SecondaryKeyCreator{   

@Override
public boolean createSecondaryKey(SecondaryDatabase arg0,
        DatabaseEntry key, DatabaseEntry data, DatabaseEntry secondKey) {
    RecordTupleBinding binding = new RecordTupleBinding();
    Record record = (Record) binding.entryToObject(data);

    try {
        secondKey.setData(data.getData());
    } catch (Exception e) {
        e.printStackTrace();
    }

    return true;
}

}

score 0 · Answer 1 · answered Jun 15 '12 at 23:57

0

Although I am nota an expert on the topic, let me try to help you.

According to Oracle documentation, "If a primary database is to be associated with one or more secondary databases, it may not be configured for duplicates". Do you have an association from this database? If so, this may be the reason.

I hope it helps.

answered Jun 15 '12 at 23:57

rlinden

2,053
1
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However, the doc also says that that a secondary database "always associated with a single primary database." One can't open a secondary database if no primary database is associated with it. I have one primary and one secondary database. – ms1013 Jun 16 '12 at 00:09
@Matt - read the answer again. Note it says "one or more". Your comment implies that you've misread that as "more than one". What the documentation seems to be saying is that you CANNOT have duplicates if you are using a secondary database. – Stephen C Jun 16 '12 at 03:10

score 0 · Answer 2 · answered Jun 16 '12 at 17:47

0

A secondary database is needed and required to allow duplicates. The above works if

secondKey.setData(data.getData());

is changed to

secondKey.setData(((String)record.getobjectVal()).getBytes());

answered Jun 16 '12 at 17:47

ms1013

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Duplicate Keys in Oracle Berkeley DB Java Edition

2 Answers2