Which of the following is a requirement when merging modified data into a DataSet ?
Correct answer: C. A primary key must be defined on the DataTable objects
- A. The DataSet schemas must match in order to merge
- B. The destination DataSet must be empty prior to merging
- C. A primary key must be defined on the DataTable objects
- D. A DataSet must be merged into the same DataSet that created it.
Explanation
During a merge, a primary key lets ADO.NET match modified source rows with their corresponding destination rows instead of treating them as new rows. Matching schemas or an empty destination is not generally required.
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