com.sleepycat.db
Interface DbDupCompare

public interface DbDupCompare

An interface specifying a comparison function, which imposes a total ordering on the duplicate data items in a Btree database.

Method Summary

int	compareDuplicates(Db db, Dbt dbt1, Dbt dbt2) The DbDupCompare interface is used by the Db.setDuplicatelicateCompare method.

Method Detail

compareDuplicates

public int compareDuplicates(Db db,
                             Dbt dbt1,
                             Dbt dbt2)

The DbDupCompare interface is used by the Db.setDuplicatelicateCompare method.

Parameters:

db - the enclosing database handle.

dbt1 - a Dbt representing the application supplied data item.

dbt2 - a Dbt representing the current tree's data item.

Returns:

The dup_compare_fcn function must return an integer value less than, equal to, or greater than zero if the first data item parameter is considered to be respectively less than, equal to, or greater than the second data item parameter. In addition, the comparison function must cause the data items in the set to be well-ordered. The comparison function must correctly handle any data item values used by the application (possibly including zero-length data items). The data and size fields of the Dbt are the only fields that may be used for the purposes of this comparison, and no particular alignment of the memory to which the data field refers may be assumed.