Data mapping for system migrations or interfacing is one of those tasks where the first 90% of the work takes 90% of the time, and the last 10% takes another 90% of the time.
With legacy systems you are sure to come face to face with a lack of knowledge about certain fields: what they mean, and how they impact the system and the business.
We have two open source tools that expedite mapping significantly.
Data Content Analyzer, examines every field in your database and lists the range of values, and the top ten values by frequency, along with basic descriptive information and number of rows of the parent tables.
Data Usage Summary, lists every source code statement where every database field is used.
Having this data at your fingertips in a quickly searchable spreadsheet greatly expedites mapping discussions.
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