Contents

• pg_complex
  • Installation
  • Dependencies
  • Copyright and License

pg_complex

PG_complex is a PostgreSQL C-language extension that implements a user-defined type (UDT) for complex numbers. It is intended for educational purposes, not production use.

(Seriously, why would anyone store complex numbers in a relational database?)

The UDT demonstrates the use of composite types.

A discussion of the creation and use of this extension can be found at http://invariantproperties.com/2015/07/17/extending-postgresql-complex-number-data-type/.

Installation

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

Once pg_complex is installed, you can add it to a database. If you're running PostgreSQL 9.1.0 or greater, it's a simple as connecting to a database as a super user and running:

CREATE EXTENSION pg_complex;

If you've upgraded your cluster to PostgreSQL 9.1 and already had pg_complex installed, you can upgrade it to a properly packaged extension with:

CREATE EXTENSION pg_complex FROM unpackaged;

For versions of PostgreSQL less than 9.1.0, you'll need to run the installation script:

psql -d mydb -f /path/to/pgsql/share/contrib/pg_complex.sql

If you want to install pg_complex and all of its supporting objects into a specific schema, use the PGOPTIONS environment variable to specify the schema, like so:

PGOPTIONS=--search_path=extensions psql -d mydb -f pg_complex.sql

Dependencies

The pg_complex data type has no dependencies other than PostgreSQL.

Copyright and License

Copyright (c) 2015 Bear Giles bgiles@coyotesong.com.