Data binding describes the relationship between an element in a consumer structure and a column in a rowset or parameter in a text command. A consumer uses the binding structure to communicate to the provider how it expects the data to be transferred from the provider to the consumer's buffer, and vice versa. The binding structure includes information such as the column or parameter being accessed, the data type in the consumer's buffer, the offset to the data in the consumer's data structure, the amount of space available for the data value, and the precision and scale for numeric values. For columns containing OLE objects, the consumer can also request the interface that must be returned to the consumer when the object is fetched.
An accessor is a group of binding structures. It enables consumers to define simultaneous access to multiple columns or parameters and enables providers to optimize access to these multiple columns or parameters.