Which Process reads data from Datafiles?

1 Answer

Answer :

Server Process - There is no background process which reads data from datafile or database buffer. Oracle creates server processes to handle requests from connected user processes. A server process  communicates with the user process and interacts with Oracle to carry out requests from the associated user  process. For example, if a user queries some data not already in the database buffers of the SGA, then the  associated server process reads the proper data blocks from the datafiles into the SGA. Oracle can be configured to vary the number of user processes for each server process.  In a dedicated server configuration, a server process handles requests for a single user process. A shared server configuration lets many user processes share a small number of server processes, minimizing the  number of server processes and maximizing the use of available system resources.

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