lib4d_sql is a C library that provides the required functions (connect, prepare, execute, etc.) for writing an SQL client for 4D databases. It uses the public 4D SQL protocol, which is supported by 4D products since version 11. It is already used by the PDO_4D Open Source project, and it might be used to provide others drivers for JDBC, ADO, or ActiveRecord.
Processdsn consumes RFC 3464 delivery status notification email messages, writing a summary of the notification to a SQL database. Notifications may indicate successful delivery, a delay in delivery, or delivery failure. The database is designed to be exposed restfully by the mod_processdsn module for Apache httpd, but can queried directly if necessary.