Sun Match Engine Match Configuration File Format (Understanding the Sun Match Engine)

Understanding the Sun Match Engine

Sun Match Engine Match Configuration File Format

The match configuration file is divided into two sections. The first section consists of one line that indicates the matching probability type. The second section consists of the matching rules to use for each match field.

Match Configuration File Sample

Following is an excerpt from the default match configuration file. This excerpt illustrates the components that are described in the following sections.

ProbabilityType            1

FirstName              15  0   uf    0.99  0.001   15  -5
LastName               15  0   ul    0.99  0.001   15  -5
String                 25  0   ua    0.99  0.001   10  -5
DateDays               20  0   dD    0.99  0.001   10  -10 y 15      30
DateMonths             20  0   dM    0.99  0.001   10  -10 n
DateHours              20  0   dH    0.99  0.001   10  -10 y 30      60
DateMinutes            20  0   dm    0.99  0.001   10  -10 y 300 600
DateSeconds            20  0   ds    0.99  0.001   10  -10 y 75      60
Numeric                15  0   n     0.99  0.001   10  -10 y 8
Integer                15  0   nI    0.99  0.001   10  -10 n
Real                   15  0   nR    0.99  0.001   10  -10 n
Char                   1   0   c     0.99  0.001   5   -5
pro                    15  0   p     0.99  0.001   10  -10 20 5 5

Probability Type

The first line of the match configuration file defines the probability type to use for matching. Specify “0” (zero) to use m-probabilities and u-probabilities to determine a field’s match weight; specify “1” (one) to use agreement and disagreement weight ranges. If the probability type is set to use agreement and disagreement weight ranges, the m-prob and u-prob columns in the matching rules section are ignored. Likewise, if the probability type is set to use m-probabilities and u-probabilities, the agreement-weight and disagreement-weight columns in the matching rules section are ignored. The default is to use agreement and disagreement weight ranges because they are more intuitive.

Matching Rules

The section after the first line of the match configuration file contains match field rows, with each row defining how a certain data type or field will be matched. The syntax for this section is:

match-type size null-field function m-prob u-prob agreement-weight disagreement-weight parameters

Table 1 describes each element in a match field row.

Table 1 Match Configuration File Columns


Column Number	Column Name	Description
1	match-type	A value that indicates to the Sun Match Engine how each field should be weighted. Each field included in the match string (the MatchingConfig section of the Match Field file) must have a match type corresponding to a value in this column.
2	size	The number of characters in the field on which matching is performed, beginning with the first character. For example, to match on only the first four characters in a 10-digit field, the value of this column should be “4”.
3	null-field	An index that specifies how to calculate the total weight for null fields or fields that only contain spaces. You can specify any of the following values: 0 - (zero) If one or both fields are empty, the weight used for the field is 0 (zero). 1 - (one) If both fields are empty, the agreement weight is used; if only one field is empty, the disagreement weight is used. a# - An “a” followed by a number specifies to use the agreement weight if both fields are empty. The agreement weight is divided by the number following the “a” to obtain the match weight for that field. If no number is specified, the default is “2”. You can specify any number from 1 through 10. d# - A “d” followed by a number specifies to use the disagreement weight if only one field is empty. The disagreement weight is divided by the number following the “d” to obtain the match weight for the field. If no number is specified, the default is “2”. You can specify any number from 1 through 10. Note – In the above descriptions, the agreement and disagreement weights are either specified in this file or calculated using a logarithmic formula based on the m and u-probabilities (depending on the probability type).
4	function	The type of comparison to perform when weighting the field. For information about the available comparison functions, see Match Configuration Comparison Functions for Sun Match Engine (Repository).
5	m-prob	The initial probability that the specified field in two records will match if the records match. The probability is a double value between 0 and 1, and can have up to 16 decimal points.
6	u-prob	The initial probability that the specified field in two records will match if the records do not match. The probability is a double value between 0 and 1, and can have up to 16 decimal points.
7	agreement-weight	The matching weight to be assigned to a field given that the fields match between two records. This number can be between 0 and 100 and can have up to 16 decimal points. It represents the maximum match weight for a field.
8	disagreement-weight	The matching weight to be assigned to a field given that the fields do not match between two records. This number can be between 0 and -100 and can have up to 16 decimal points. It represents the minimum match weight for a field.
9	parameters	The parameters that correspond to the comparison function specified in column 4. Some comparison functions do not take any parameters and some take multiple parameters. For additional information about parameters, see Match Configuration Comparison Functions for Sun Match Engine (Repository).