Attributes
DataFlex communicates with drivers via a DataFlex API. It is the driver’s responsibility to adhere to this API and use it to communicate directly with the back-end database. Internally, the DataFlex runtime uses this API to implement its database commands (e.g., Open, Find, SaveRecord, Get_Field_Value) and to implement the DataDictionary class interface (e.g., Request_Find, Request_Save). These are the interfaces that you will use most often.
In addition, the entire Database API is made available to developers through a set of commands (e.g., Get_Attribute, Set_Attribute) and attributes (e.g., DF_FILE_ROOT_NAME, DF_FIELD_NAME, DF_INDEX_NAME).
While all drivers must comply with the basic API, individual drivers and groups of drivers may support additional driver-specific extension APIs. Of interest are the API extensions used by the DataFlex SQL Drivers. A set of extended API attributes allows support for features that, while unique to SQL servers, are common across SQL servers. This makes it possible to take greater advantage of SQL features. Features such as managed connections, SQL filters, client-side indexes, and embedded SQL become possible. Once a developer uses these features, they may not be able to run their application on all databases (such as the Embedded database) but will still be able to run on databases using the DataFlex SQL drivers.
The list of attributes is extensive. Your application will rarely use them, as the DataFlex framework has wrapped most of these into their own interface. When needed, they are there.
Attributes are documented in the Language Reference. Some driver-specific attributes have corresponding intermediate file keywords. If so, the documentation for the attribute will list and link to the appropriate keyword. Likewise, any intermediate file keyword that has an associated attribute will list and link to the documentation for that attribute.
See Database API Attributes and Intermediate Files for more information.