Master/detail relationships: Two Drawbacks

1.The detail table must fetch and store all of its records from the application server even though it only uses one detail set at a time. This problem can be mitigated by using parameters.Limiting records with parameters
2.It is very difficult to apply updates, because client datasets apply updates at the dataset level and master/detail updates span multiple datasets. Even in a two-tiered environment, where you can use the database to apply updates for multiple tables in a single transaction, applying updates in master/detail forms is tricky.Applying updates for master/detail tables

In multi-tiered applications, you can avoid these problems by using nested tables to represent the master/detail relationship. To do this, set up a master/detail relationship between the tables on the application server. Then set the DataSet property of your provider component to the master table.
When clients call the GetRecords method of the provider, it automatically includes the detail datasets as a DataSet field in the records of the data packet. When clients call the ApplyUpdates method of the provider, it automatically handles applying updates in the proper order

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