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1. Based on Usage: DP is used to draw/pick a value for a field in Originating BC from any BC whereas MVGs is an alternative to a detail view for managing parent and related child records. It allows complex queries that span multiple BCswhich would have not been possible when displaying parent child in a detail view.
In case of DP: Originating BC=Opportunity S_OPTY, Pick BC=Account.
For MVG: Parent=Account, Child= Business Address MVG, Territory MVG, Account Team MVG)
For Example: MVG=> Account BO instance can have multiple Business Addresses as child – say BA1 (primary), BA2, BA3. The business requires that only the primary address be associated with the Account.
2. DP is associated with a Single Value Field (SVF) whereas MVG is used for Multi Value Fields (MVFs). Multi Value Field is a field in the parent C that references a field in the Child BC (not a column in a table).
3. Based on: DP pulls information from a BC with the help of JOINS whereas MVG uses multi-value links (MVLs).
4. Relationship: DP is used to implement 1:1 or M:1 whereas MVG is used for 1:M or M:M