introduction to the course

mainly we will continue on the file structure course on this course
in this course we wion't talk about DB's we will talk about Files just files
but first let's see what's the difference between File & DB
Files : DB
unstructured : Structured
need just a system : Need a DBMS

so in our file structure course how did we do it?
the sequence of steps was as follows
-Create file
-Add file
-Storing data

at the beginning files were stored in tapes which require sequential access
O(n)

Then disks appeared and it required direct access
Binary Search
O(log n)
naturally log of base 2


Indexing

but let's think for a moment what if my data is large
it will need 127 Disk access
and the optimal is from 1 to 3

this course will include these titles also
-Binary search trees
- AVL Trees
-B Trees
-B+ Trees
-Hashing