count_nulls
Provides a function that counts the number of (not) null arguments passed to it. Also provides a version for counting nulls in a JSON document, which makes it easy to count the number of nulls in a record.
Installation
To build it, just do this:
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 install
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 test PGUSER=postgres
Once count_nulls 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 count_nulls;
If you've upgraded your cluster to PostgreSQL 9.1 and already had count_nulls installed, you can upgrade it to a properly packaged extension with:
CREATE EXTENSION count_nulls 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/count_nulls.sql
If you want to install count_nulls 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 count_nulls.sql
Dependencies
The count_nulls
data type has no dependencies other than PostgreSQL.
Copyright and License
Copyright (c) 2015 Jim Nasby, Blue Treble Consulting http://BlueTreble.com