Write ✍️✍️ a Query processing and transaction processing.
Write ✍️✍️✍️ a Query processing and transaction processing
Query Processing:-
The technique used by a DBMS to process ,optimize,and execute high level queries.An internal representation of the query is then created, usually as a tree data structure called a query tree. The query can also be represented using a graph data structure called a query graph.
A query typically has many possible execution strategies and the process of selecting an appropriate one for processing a query is known as query optimization.
Transaction processing:-
A transaction can be considered as a unit of program execution that access and update various data items of a database. A transaction can be regarded as a series of reads writes of data objects.
This processing are following properties of the transaction:-
Atomicity:- Either all the operation of a transaction are carried out or none are. User need not worry about the effect of incomplete transaction.
Consistency:- Each transaction run by itself with no concurrent execution of the other transaction.
Isolation:- User should be able to understand a transaction without considering the effect of other concurrent execute transaction.
Durability:- Once the DBMS notifies the user that the transaction has been successfully completed, the changes made to the database remain even if there is a system failure.
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