First, a quick recap. XDTL ( is an XML based descriptional language designed for specifying data transformations from one database/storage to another. XDTL syntax is defined in an XML Schema document. XDTL Runtime is a lightweight ETL runtime environment that efficiently and with zero overhead handles most of the typical ETL needs. XDTL Runtime can generate SQL or SAS scripts (or any other executable instructions for that matter) based on templates processed by a template engine.

Now, the 'news' part. XDTL Runtime Version 1.0 (XDTL RT 1.0) is finished and running live! The runtime is written in Java (Sun JRE 1.6 required) and uses Velocity ( for template processing. So here's a short primer.

There are two individually addressable units of execution in XDTL: a package is a container containing tasks, both of them can be invoked by name. A task consists of steps denoting individual commands that are executed sequentially and cannot be addressed individually. Besides tasks, a package contains three collections: parameters, variables and connections. As in XSLT, $ denotes dereferencing: during execution, everything starting with $ is dereferenced and substituted with a value. In addition, everything between { and } is treated as a JavaScript expression and evaluated.   

There are file commands and database commands in XDTL. File commands usually launch operating system processes and are designed to handle files (move, compress, transfer etc.). File commands in XDTL RT 1.0 are:

get: downloads a file with a file transfer utility (ftp, scp, sftp)
put: uploads a file with a file transfer utility (ftp, scp, sftp)
unpack: unpacks a file with an archival utility (zip, arj, tar etc)
pack: pack a file with an archival utility (zip, arj, tar etc)
strip: cleanse a text file, eg. with a stream/regex utility (sed etc)
move: move files to another directory, usually for archival with timestamp
clear: remove everything related to a file/task from a working directory
log: adds a line to standard log output
exec: executes an arbitrary operating system command line (shell) command

Database commands control database operations:

read: transfers a text file into a database table, usually in staging area
write: transfer a database table into a text file
load: configured to load a file into a database table with a bulk load utility
dump: configured to dump a database table into a file with a bulk dump utility
transaction: wrapper for transaction processing
query: executes a database command (an SQL statement, a SPARQL query etc.)

Then come some control flow commands:

call: invokes another package or another task passing required parameters
if: adds basic conditional control

Finally, while the file and database commands constitute the backbone of XDTL, it's heart and soul are mappings and render commands:

mappings: define or retrieve metadata used to instantiate a procedure (SQL, SAS etc.)
render: merges a code template with corresponding mappings to produce executable SQL statement(s), SAS procedure(s) or any other form of executable code

Mappings and templates are fully decoupled and 'know nothing about each other': it's only during the rendering step that they meet each other to merge into an executable script or set of instructions. This enables a lot of novel opportunities: a specific set of mappings can be used with different templates for different purposes, a specific template can be reused many times with different mappings to handle different data sources, a mapping representing some business logic can be ported to another platform by rendering with another template etc.  Splendid!