What are the two types of file access? What is the difference between these two?
The two types of file access are as follows:
Sequential Access: In sequential access, data is read from or written to a file in a sequential order, one after the other. To access a specific piece of data, the program must start reading from the beginning of the file and continue until it reaches the desired data or the end of the file. Similarly, when writing data, the program appends new data to the end of the file. Sequential access is typically used for text files or data streams that are processed in a linear manner. Examples include reading lines from a text file, processing a data file record by record, or streaming data from a source to a destination.
Random Access: In random access, data can be read from or written to a file in any order, without the need to read or write sequentially from the beginning. Random access allows direct access to specific locations within the file, so data can be accessed at any position without reading through the entire file. This is achieved through the use of file pointers or offsets, which indicate the current position in the file. Random access is common in binary files or data structures where quick access to specific data elements is required. Examples include accessing a specific record in a database file or seeking to a specific byte in a binary file to read or modify data.
Difference between Sequential Access and Random Access:
The main difference between sequential access and random access lies in how data is accessed:
Data Access Pattern:
Access Efficiency:
File Organization:
In summary, sequential access reads or writes data in a linear order from the beginning to the end of the file, while random access allows direct access to specific positions within the file for efficient data retrieval. The choice between sequential and random access depends on the nature of the data and the access pattern required by the program.