This chapter should have given you a good feel for how to build C applications using ecpg. Don't let the last section throw you off too muchecpg isn't all that well suited to processing dynamic SQL (at least in comparison to libpq or libpgeasy).
The ecpg preprocessor and library are remarkably well designed for building complete PostgreSQL applications quickly.
If you don't need to process dynamic queries, I think that ecpg is the quickest and easiest way to connect a C application to a PostgreSQL database. If you do need to handle dynamic queries, you should consider coding the static parts of your application using ecpg and using libpq (or libpgeasy) for the dynamic parts.
Most of the features in ecpg come from the SQL3 standard and you should find that it is reasonably easy to move embedded SQL applications among various databases (assuming that you haven't used too many "special" features).
Part I: General PostgreSQL Use
Introduction to PostgreSQL and SQL
Working with Data in PostgreSQL
PostgreSQL SQL Syntax and Use
Part II: Programming with PostgreSQL
Introduction to PostgreSQL Programming
The PostgreSQL C APIlibpq
A Simpler C APIlibpgeasy
The New PostgreSQL C++ APIlibpqxx
Embedding SQL Commands in C Programsecpg
Using PostgreSQL from an ODBC Client Application
Using PostgreSQL from a Java Client Application
Using PostgreSQL with Perl
Using PostgreSQL with PHP
Using PostgreSQL with Tcl and Tcl/Tk
Using PostgreSQL with Python
Npgsql: The .NET Data Provider
Other Useful Programming Tools
Part III: PostgreSQL Administration
Introduction to PostgreSQL Administration
Internationalization and Localization
Replicating PostgreSQL Data with Slony