Mapping in Biztalk(between different documnts or schemas)

The transformation defined in a map can be simple, such as copying a name and address from one document to another. Direct data copies like this are expressed by using a link, which is shown in BizTalk Mapper as a line connecting the appropriate elements in the source schema with their counterparts in the destination schema. More complex transformations are also possible by using functoids. A functoid is a chunk of executable code that can define arbitrarily complex mappings between XML schemas, and BizTalk Mapper represents it as a box on the line connecting the elements being transformed. Because some of those transformations are fairly common, BizTalk Server 2004 includes a number of built-in functoids. These built-in functoids are grouped into categories that include the following:·
Mathematical functoids.
Perform operations such as adding, multiplying, and dividing the values of fields in the source document and storing the result in a field in the target document.
Conversion functoids.
Convert a numeric value to its ASCII equivalent and vice-versa.
Logical functoids.
Used to determine whether an element or attribute should be created in the target document based on a logical comparison between specified values in the source document. Those values can be compared for equality, greater than/less than, and in other ways.
Cumulative functoids.
Compute averages, sums, or other values from various fields in the source document, and then store the result in a single field in the target document.Database functoids. Access information stored in a database