Introduction to Storing and Retrieving
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What is Storing and Retrieving? How does it work?
Storing and retrieving is a two part process which involves the storage of data on some kind of storage medium so it can be preserved and then later retrieved for use by another process at a later time. Typically when data is stored, the method of data representation changes, e.g. data from the computer in electrical form is stored onto the hard disk in magnetic form. This is also true for retrieving as data may be converted back from magnetic data into electrical signals for use by the computer.
Storing and retrieving is a two part process which involves the storage of data on some kind of storage medium so it can be preserved and then later retrieved for use by another process at a later time. Typically when data is stored, the method of data representation changes, e.g. data from the computer in electrical form is stored onto the hard disk in magnetic form. This is also true for retrieving as data may be converted back from magnetic data into electrical signals for use by the computer.
The Role of Storing and Retrieving
To Allow Other Processing to Take Place
When data is processed by the processor, the processed data needs to be taken out of the processor before any other data can be processed. This involves storing this data on the computer’s primary (e.g. RAM) or secondary (e.g. Hard disk) storage mediums. Once the processor is freed up, the processor can retrieve and process another portion of data from storage.
When data is processed by the processor, the processed data needs to be taken out of the processor before any other data can be processed. This involves storing this data on the computer’s primary (e.g. RAM) or secondary (e.g. Hard disk) storage mediums. Once the processor is freed up, the processor can retrieve and process another portion of data from storage.
To Allow for a Temporary Halt in the System
Usually, data is processed over multiple sessions making it necessary to have a method of retaining the previously processed data for the next session. This involves storing any pre-processed data on a storage medium while the system is halted. An example of this is a student completing an assignment. The student usually does not complete the assignment in one go and needs to store the assignment data until they are ready to work on it again.
Usually, data is processed over multiple sessions making it necessary to have a method of retaining the previously processed data for the next session. This involves storing any pre-processed data on a storage medium while the system is halted. An example of this is a student completing an assignment. The student usually does not complete the assignment in one go and needs to store the assignment data until they are ready to work on it again.
For Backup and Recovery
A backup is the process of making copies of data on permanent, secondary storage mediums. To retrieve this data once a backup is made, the opposite process of recovery occurs. The main purpose of this is to prevent data loss in the event that the original data is damaged or lost. Backups can consist of full or partial backups. A full back up copies all data contained on a system where as a partial backup copies any data that has been created or modified since the last backup. The way this is determined is by an archive attribute given to each file which states whether the file has been created or changed. Typically whenever a file is backed up, the file has its archive attribute set to false. The only time this does not happen is when a differential backup occurs. |
To Assist the Transfer of Data/Information
When data is accessed over a network or the internet, you are essentially retrieving data off of a remote storage device. This can only occur if data is first stored on the remote computer so other computers can retrieve this data. When retrieved, the data is stored locally on the retrieving computer so further processing can occur and the resulting data displayed to the user.
When data is accessed over a network or the internet, you are essentially retrieving data off of a remote storage device. This can only occur if data is first stored on the remote computer so other computers can retrieve this data. When retrieved, the data is stored locally on the retrieving computer so further processing can occur and the resulting data displayed to the user.