solentware-base 3.0.1

Database Record definition classes

Contents

• Description

• Installation Instructions

• Notes

• Restrictions

Description

This package provides a record-level API to a variety of database engines in the style of bsddb3 cursors.

A record contains a key and a value, (key, value) say. Indexes contain records which invert this as (F(value), key). F() would return a substring of value for example.

The value could be a pickled class instance, or perhaps more safely a string which can be evaluated by the ast.literal_eval function.

Interfaces exist for:

• bsddb3

• DPT

• sqlite3

• apsw

At least one of the database engines supported by these interfaces must be installed.

Installation Instructions

Install the package by typing

python setup.py install

at the command prompt with setup.py in the current directory.

You may need to give the path and version of Python depending on your system’s configuration:

<path to python>/python<version> setup.py install

For example

C:\Python33\python setup.py install

on Microsoft Windows or

python3.3 setup.py install

on Unix-like systems.

Use Python 3.3 or later.

Notes

The sqlite3 interface was added because sqlite3 became the only database engine supporting ordered keys included in the Python distribution when bsddb was dropped at Python 3.

I have not yet succeeded in building bsddb3 on Microsoft Windows. I assume this package will work with bsddb3 on Microsoft Windows.

DPT is Microsoft Windows only. It is included because it represents record sets in indexes using bitmaps when efficient to do so, and uses bitmaps to do boolean logic on record sets.

Restrictions

Python 3.4 and 3.5 are removed from runtime dependencies because delete record unittest results using Python’s sqlite3 interface to Sqlite 3 are erratic.

The equivalent unittest results using the apsw interface to Sqlite 3 are both identical and not erratic for Python 3.3, 3.4, and 3.5