Modules

Here is a list of all modules:

Connection classes	The connection classes are where the use of a database begins
Errorhandler
Exception classes	These exception classes follow, roughly, the two-level hierarchy defined by the PostgreSQL error codes (see Appendix A of the PostgreSQL documentation corresponding to your server version)
Notifications and Receivers	"Observer" base class for notifications
Performance features	If your program's database interaction is not as efficient as it needs to be, the first place to look is usually the SQL you're executing
Prepared statements	Prepared statements are SQL queries that you define once and then invoke as many times as you like, typically with varying parameters
String conversion	For purposes of communication with the server, values need to be converted from and to a human-readable string format that (unlike the various functions and templates in the C and C++ standard libraries) is not sensitive to locale settings and internationalization
String escaping	Binary data corresponding to PostgreSQL's "BYTEA" binary-string type
Transaction classes	Abstract base class responsible for bracketing a backend transaction
Transactor framework	Wrapper for transactions that automatically restarts them on failure
Utility functions