Abstract: A b-tree may contain multiple keys. Each key may contain multiple column values of different types. In order to allow quick byte by byte comparison of the keys, a normalized form of the keys may be determined by transforming each column value, through a type specific transformative function, into a normalized form. This normalized form allows keys to be quickly compared and may be used in compressing the underlying b-tree. Each normalized key is compressed relative to the previous key by replacing the common prefix bytes with a common prefix length byte containing the number of bytes in common between the key and the previous key. The compressed keys are stored sequentially in memory with no gaps in between.

Abstract: A b-tree may contain multiple keys stored in a normalized form. This normalized form allows keys to be quickly compared and may be used in compressing the underlying b-tree. Each normalized key is compressed relative to the previous key by replacing the common prefix bytes with a common prefix length byte containing the number of bytes in common between the key and the previous key. The compressed keys are stored sequentially in memory with no gaps in between.

Abstract: Contacts are stored in memory on a mobile device with a limited input device containing input points. Each input point corresponds to a subset of the alphabet. For each contact, a string comprising characters representing the input points that correspond to the letters of the alphabet contained in the name of the contact is generated and saved with the contact in the memory. When a user desires to retrieve a contact, the user presses the input point that corresponds to the subset of the alphabet containing the first letter in the name of that contact. A prefix search for the character representing that input point is performed on the saved generated strings. Any contacts containing a matching string are then presented to the user.