Matching Records Between Two Files

Using Unique Identifiers

The most reliable way of matching records is to use a common unique identifier for the two files. For example an Order Number, Transaction ID or an SKU. In Differencia a unique identifer can span multiple fields. For example an Order Number, combined with an Item Number.

1. Select each file by choosing File > Open twice
2. For File 1, in the list of fields check the ID checkbox for each field that comprises the unique identifier
3. Repeat step 2. for File 2
4. Select each pair of identity fields in turn and choose Comparison > Add Field Mapping
5. Select each pair of data fields un turn and choose Comparison > Add Field Mapping
6. Choose Comparison > Compare

Using Data Matching

Common, unique identifiers are not always available between two files. In this circumstance, key data fields that should match between the two files can be used to match records:

1. Open the two files to be compared, by choosing File > Open twice
2. For File 1, in the list of fields, check the ID check box for each key data item
3. Repeat step 2. for File 2
4. Select each pair of data fields in turn and choose Comparison > Add Field Mapping

Use the minimum number of data fields required to ensure that each record is unique identified.

5. Select each remaining pair of data fields in turn and choose Comparison > Add Field Mapping
6. Choose Comparison Compare

NB: If multiple records are found with the same values for the identity data fields, the results of the comparison are undefined

Also note that when using data matching, if there is a difference in the data fields being used the match records, the differences will be displayed as missing record differences in each file, rather than specific field differences.

Using Ordered Comparisons

If unique identifiers, or data matching cannot be used, or if the data is already in the same order, Differencai can run an ordered comparison:

1. Open the two files to be compared by choosing File > Open twice
2. In the list of fields, select each paird of data fields to be compared in turn, and choose Comparison > Add Field Mapping
3. Choose Comparison > Compare

Note that if there is a missing record in one of the files, subsequent records are likely to be displayed with differences and each record in one file will not be compared with the corresponding record in the other file.