In the phase of transferring data from a transactional database to a data warehouse, the builders create the files from transactional databases and save them on the server that will hold the data warehouse.

Extraction phase

Explanation: Transactional database is the data collection capable of undoing the transaction that has not been correctly done. Data warehouse id the place where transaction data is transmitted where different types of databases are stored.

The transmission of the information from transactional database to data warehouse is defined in the extraction phase.The extraction phase works by transforming the data into a particular format. It copes the transactional databases's data to the warehouse by making separate space for deposition of data

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