### Contents

- pair 0.1.0
  - Dependencies
  - Copyright and License

# pair 0.1.0

This library contains a single PostgreSQL extension, a key/value pair data type called `pair`, along with a convenience function for constructing key/value pairs. It's just a simple thing, really: a two-value composite type that can store any type of value in its slots, which are named "k" and "v".

The `pair` data type was created as an inspiration, as documented in this blog post. Give it a read if you're interested in the context of its creation.

To build it, just do this:

    make
    make installcheck
    make install

If you encounter an error such as:

    "Makefile", line 8: Need an operator

You need to use GNU make, which may well be installed on your system as `gmake`:

    gmake
    gmake install
    gmake installcheck

If you encounter an error such as:

    make: pg_config: Command not found

Be sure that you have `pg_config` installed and in your path. If you used a package management system such as RPM to install PostgreSQL, be sure that the `-devel` package is also installed. If necessary tell the build process where to find it:

    env PG_CONFIG=/path/to/pg_config make && make installcheck && make install

And finally, if all that fails (and if you're on PostgreSQL 8.1 or lower, it likely will), copy the entire distribution directory to the `contrib/` subdirectory of the PostgreSQL source tree and try it there without `pg_config`:

    env NO_PGXS=1 make && make installcheck && make install

If you encounter an error such as:

    ERROR:  must be owner of database regression

You need to run the test suite using a super user, such as the default "postgres" super user:

    make installcheck PGUSER=postgres

## Dependencies

The `pair` date type has no dependencies other than PostgreSQL.

## Copyright and License

Copyright © 2010 David E. Wheeler.

This module is free software; you can redistribute it and/or modify it under the PostgreSQL License.

Permission to use, copy, modify, and distribute this software and its documentation for any purpose, without fee, and without a written agreement is hereby granted, provided that the above copyright notice and this paragraph and the following two paragraphs appear in all copies.

In no event shall David E. Wheeler be liable to any party for direct, indirect, special, incidental, or consequential damages, including lost profits, arising out of the use of this software and its documentation, even if David E. Wheeler has been advised of the possibility of such damage.

David E. Wheeler specifically disclaims any warranties, including, but not limited to, the implied warranties of merchantability and fitness for a particular purpose. The software provided hereunder is on an "as is" basis, and David E. Wheeler has no obligations to provide maintenance, support, updates, enhancements, or modifications.