Like the ability to write user defined functions to process data in SQL queries in whatever language you want, for example. Language handlers have long been available not only for SQL, C, and PL/PGSQL (PostgreSQL's variant of Oracle's PL/SQL), but also TCL, Perl, and Python. Third party language handlers are available for Java, PHP, and many more languages. Yes, you can run PHP inside your PostgreSQL database.....
Now new data types are pretty much C-only, but you can also create a lot of the same functionality using composite types and sql. Composite types (and even arrays of composite types) can be tuple elements.
Add to this the object-oriented-inspired features, allowing you to use multiple inheritance to mix in tables and create common interfaces to data (both features older than PostgreSQL's use of SQL).
What this means is you can do some extremely advanced db-stuff with PostgreSQL. This can include:
- I want to create a common interface for notes but avoid a global notes table.
- I want to scan a series of images stored in the db for those matching an algorithm in a Java library showing which are likely images of sunsets.
- I want to add support for a third party Java full text search engine into the back-end so I can call its functions from inside SQL queries.
Now new data types are pretty much C-only, but you can also create a lot of the same functionality using composite types and sql. Composite types (and even arrays of composite types) can be tuple elements.
Add to this the object-oriented-inspired features, allowing you to use multiple inheritance to mix in tables and create common interfaces to data (both features older than PostgreSQL's use of SQL).
What this means is you can do some extremely advanced db-stuff with PostgreSQL. This can include:
- I want to create a common interface for notes but avoid a global notes table.
- I want to scan a series of images stored in the db for those matching an algorithm in a Java library showing which are likely images of sunsets.
- I want to add support for a third party Java full text search engine into the back-end so I can call its functions from inside SQL queries.