These following are the advantages of DBMS-
Data Redundancy- A main difficulty was that a lot of applications used their own special files of data. Thus, some data items were common to some applications. In a bank, as in the same customer name may appear in a checking account file, a savings account file and an instalment loan file. Moreover, even though it was at all times the customer name, the related field usually had a different name in the range of account files. Thus, CNAME in checking account file became SNAME in the savings account file and INAME in instalment loan file. The same field also has a unlike length in the variety of files. As in CNAME can be up to 20 characters, but SNAME and INAME might be limited to 15 characters. This redundancy increased the overhead expenditure of maintenance and storage. Data redundancy increased the risk of inconsistency in the midst of the various versions of common data.
Assume a customer''s name was changed. The name field may be immediately updated in checking account file, updated next week in a savings account file and updated mistakenly in instalment loan file. Greater than time, discrepancies could cause serious degradation in the quality of information contained in data files. Database systems can remove data redundancy, as all applications share a common pool of data. Important information such as customer name would be appearing just once in the database.
Thus, we can enter a name or change once and know that applications would be accessing consistent data.
Poor Data Control- In the file system, there was no middle control at the data element level. It was a common for the same data element to have multiple names, depending on file it was in.
At a more fundamental level, there is at all times the chance that a choice of departments of a company would be inconsistent in their terminology.
Inadequate Data Manipulation Capabilities- Indexed sequential files allow the applications to access a particular record by a key such as Product. As in if we knew the Product for the table, it is easy to access a record in table. Imagine we want a set of records. It is not possible to obtain set of records using file system because they are unable to provide strong connections between data in unlike files. Database systems were specifically developed to make the interrelating of data in changed files.
Excessive Programming Effort- A new application program repeatedly required a totally new set of file definitions. Though an existing file might contain some of the data needed, the application often important a number of other data items. As the result, programmer had to recode the definitions of needed data items from the existing file in addition to definitions of all data items. Thus, in file-oriented systems, there was heavy interdependence between programs and data.
Database provides a departure between programs and data, so that programs could be somewhat independent of the details of data description. By providing access to pool of shared data and by supporting powerful data manipulating languages, database systems abolish a large amount initial and protection programming.