FIX Schema Editor

Schema editor is a graphical tool to view and modify FIX schemas in QWFIX Enterprise Manager.

The QWFIX Enterprise Manager manages all FIX schema information in the repository. A set of standard schema from FIX version 4.0 to 5.0SP1 (with FIX Transport Schema 1.1) is automatically installed upon the installation of a new instance of QWFIX Repository Server.

Note: Users shouldn't directly modify the standard FIX schemas. Instead, users should create their own versions of schemas by deriving from a given version of standard schema.

General Rules of Customizing Schema

The QWFIX session uses the schema information to optimize message encoding/decoding, message validation and memory management. Customizing FIX schema is very important in the business logic design in QWFIX system. The following are some general rules of customizing FIX schemas.

• The custom schema should be derived from the standard schema with the same version. For example, if the user wants to develop a trading system that uses FIX version 4.2, it should create a custom schema derived from the standard FIX version 4.2.
• The customized schema should not "alter" the standard schema it derives from. For example, user can not modify the header and trailer definition in the derived schemas. Also user can not delete derived fields in the derived schemas. QWFIX Enterprise Manager is smart enough to enforce that rule.
• In custom schema, definition of unused tags should be excluded from FIX message definitions. For example, if the schema is used to trade equities, the tags used in sending option/future/forex orders should be removed from the NewOrderSingle message definition.
• Custom tags (FIX dialects) should be added to custom schema instead of standard schema.

In the following chapters we will walk through features of FIX schema editor in QWFIX Enterprise Manager.

Figure 1.1: FIX Schema Editor