The application programmer will invoke the

MATCH

Service passing a Function, the name of a Scheme to be used and two records that need to be matched.

The

MATCH

Service will call all the Methods specified in the Scheme definition and pass to each Method the fields for it to match.

Depending on the Method, other internal SSA-NAME3 Services may be called on to pre-process the fields. The Methods and which Services they call are listed below:

Method	Description	Calls Internal Service
N3SCC	String Matching	Cleaning
N3SCD	Date Matching	Cleaning
N3SCE	Year Matching	none
N3SCF	Pattern Matching	none
N3SCG	Exact Matching	none
N3SCL	Name Matching	Cleaning Formatting Word Stabilization Multi-Valued Field Processing

For more information on the other Services called by a

MATCH

method, refer to the relevant chapter in this guide.

Each Method is coded to try to achieve the best possible match for the fields it is comparing, and in doing this it may try a number of different approaches. The final results from all of the Methods are then weighted and combined to produce an overall total result for the two records. One representation of this result is a score between 0 and 100.

For more information on how a score is calculated, see the

Weights in the Matching Scheme Definition

chapter in the

DEFINITION and CUSTOMIZATION GUIDE FOR SSA-NAME3 SERVICE GROUPS

.

Once control is passed back to the caller, the application program should use the overall record match result on which to base subsequent processing decisions. For example, if a Score was requested, the decision may be to process only records which exceeded a score limit. If more detail is required, the application can also request access to the individual results returned by each Method via the Method Table (MTBL).