Databases Reference
In-Depth Information
Consumers of the data can fetch complete
docs or specific data elements with XPath.
Operational data store
Queries
Trading system
Ad hoc querying
Native XML
database
(MarkLogic)
Trading system
Events
Workflow
Trading system
Clearing and
settlement
Books and
records
Reconciliation
Trade capture and
risk management systems
write trade data to the ODS,
where they are stored
as XML documents.
All XML data
elements get
indexed upon
ingestion.
Post-trade-processing workflows
are triggered by events as soon as
new data is inserted.
Systems can attach
additional data, e.g., a
confirmation PDF can
be attached to a
trade document.
Figure 5.13
Financial derivatives are stored in a native XML database being used as an
ODS. Trading systems send XML documents for each trade or contract directly to the
database where each element is directly and immediately indexed. Update triggers
automatically send event data to a workflow system and system users use simple XPath
expressions to perform ad hoc queries.
The bank's new system was ideal as a centralized store for the highly variable deriva-
tives contracts. Since MarkLogic supports
ACID
transactions and replication, the bank
maintained the reliability and availability guarantees it had with its
RDBMS
. MarkLogic
also supports
event triggers
on document collections. These are scripts that are exe-
cuted each time an
XML
file is inserted, updated, or deleted.
Whereas
RDBMS
s require every record in a database to have the same structure
and data types, document stores are more flexible and allow organizations to capture
the variations in their data in a single database. As we move to our next section, we'll
take a look at the major benefits of using a native
XML
document store.
5.7.3
Business benefits of moving to a native XML document store
The move to a document-centric architecture resulted in the following tangible bene-
fits to the organization:
Faster development
—New instrument types added to the system by the front office
traders didn't require additional software development, and therefore could be
supported in a matter of hours rather than days, weeks, or even months.
Higher data quality
—As new derivatives were loaded into the system as
XML
doc-
uments, the system was able to append the document with additional
XML
