Data Structures Using C, 2nd Edition by Pearson

Files 415

The arrangement of records in a file can be different

for different situations. The file of records shown in Fig-

ure 9.3 can be arranged according to names instead of roll

numbers, i.e., in alphabetical order. The rearranged file is

shown in Figure 9.4.

It may be noted here that in the file shown in Figure 9.3,

the records were arranged according to Roll field whereas

in the file shown in Figure 9.4, the records are arranged

according to Name field. However, a record in both the

files can be identified by the field called Roll. Basically, a

field which is used to identify a particular record within a

file is called as a key field. ...