[DB-SIG] Why so many Python drivers for PostgreSQL?

[Christoph Zwerschke]

Bob Kline wrote:
 > Are the deficiencies in each of the drivers so serious that so many
 > programmers are driven to roll their own? Or are these the
 > outgrowths of ambitious student projects?

This has historical reasons. Python and PostgreSQL are both around for a 
long time and have evolved quite a bit, and there were two DBAPI 
releases. These developments prompted people to create new drivers using 
the new standards, but some of the older projects were not given up and 
modernized as well. PyGreSQL started even before DBAPI, but is still 
maintained and quite stable; it provides the old interface in addition 
to a newer DBAPI 2 module. pyPgSQL has the special feature of returning 
rows as dictionary. Psycopg2 is more modern, sophisticated (built-in 
connection pooling) and can be considered the mainstream. Then of 
course, there are also drivers for platforms different from traditional 
CPython, such as JDBC, .NET, pure Python drivers etc.

-- Christoph