[Haskell-cafe] Re: HDBC or HSQL

[John Goerzen]

On 2007-07-25, George Moschovitis <george.moschovitis at gmail.com> wrote:
> I am a Haskell newbie and I would like to hear your suggestions regarding a
> Database conectivity library:
>
> HSQL or HDBC ?
>
> which one is better / more actively supported?

I am the author of HDBC, so take this for what you will.

There were several things that bugged me about HSQL, if memory serves:

 1) It segfaulted periodically, at least with PostgreSQL

 2) It had memory leaks

 3) It couldn't read the result set incrementally.  That means that if
 you have a 2GB result set, you better have 8GB of RAM to hold it.

 4) It couldn't reference colums in the result set by position, only by
 name

 5) It didn't support pre-compiled queries (replacable parameters)

 6) Its transaction handling didn't permit enough flexibility

I initially looked at fixing HSQL, but decided it would be easier to
actually write my own interface from scratch.

HDBC is patterned loosely after Perl's DBI, with a few thoughts from
Java's JDBC, Python's DB-API, and HSQL mixed in.

I believe it has fixed all of the above issues.  The HDBC backends that
I've written (Sqlite3, PostgreSQL, and ODBC) all use Haskell's C memory
management tools, which *should* ensure that there is no memory leakage.

I use it for production purposes in various applications at work,
connecting to both Free and proprietary databases.  I also use it in my
personal projects.  hpodder, for instance, stores podcast information in
a Sqlite3 database accessed via HDBC.  I have found HDBC+Sqlite3 to be a
particularly potent combination for a number of smaller projects.

http://software.complete.org/hdbc/wiki/HdbcUsers has a list of some
programs that are known to use HDBC.  Feel free to add yours to it.

-- John