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• The materialized view should only use transactional tables, either micromanaged or ACID.
• If the materialized view definition contains a Group By clause, the materialized view should be stored in an ACID table, since it needs to support MERGE operation. For materialized view definitions consisting of Scan-Project-Filter-Join, this restriction does not exist.  

In additionA rebuild operation acquires an exclusive write lock over the materialized view, i.e., for a given MVmaterialized view, only one incremental maintenance operationrebuild operation can be executed at a given time.

Materialized view lifecycle

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