File Organization Flashcards
Indexed Sequential file Access
Ordered data within an index
Sequential Access
One record after another
Hashing algorithms
Direct computation of storage location
Direct/Random Access
Efficient data retrieval using hash function
How to compare hashing algorithms
Compare the number of collisions that occur when given an example data set
How is The overall efficiency of a hashing algorithm determined
It’s determined by the number of records placed in the same block
How do indexed sequential files work
They contain an index that groups the data into logical chunks. So when searching for a file you first only have to search for the chunk.
How does indexing files make the addition of files more complicated
Each time a record is added to a group then the start position of all subsequent chunks will be different, this means that all subsequent points will need to be updated
How would you make indexed files more efficient if it takes a long time to search through the index
Add another layer of indexing
What is the ultimate goal of multi-level index sequences
To limit the number of times a file is accessed