Preperation for Digital Assitant JOB
August 31, 2019
Introduction to Data Structures
Arrays
 Array is a random access data structure

Linked List is a sequential data structure a. Advantages of linked list are we can add data dynamically at any point of time, Size of the array need not mention at the start of the time.
STACKS

First In Last Out
QUEUE

First in First Out
TREES

Binary tree is a tree which has left node and right node Graph Theroy is study of relationships between edges and vertexes. In graph theory tree is an undirected, connected and cyclic graph.
Depth first traversal
InOrder Traversal
 In this preorder traversal we will go left, root and then right node.
PreOrder Traversal
 In this preorder traversal we will go root,left and then right node.
PostOrder Traversal
 In this preorder traversal we will go left,right and then root node.
Bipartite graph
Cyclic graph
Acyclic graph
Searching and Sorting
Linear Search
Linear search is a way to find an element with in a list by sequential going through each one
Time complexity N
Binary Search
Binary search works on the sorted array. The comparsion of the element to be found is done at the half of the array .
If the match is not found then the element goes to the first half or the second half based on the comparision.
Time complexity **logN**
Sorting
Selection Sort
In this case the minimum value is found and swaps with the first element and so on till all the elements are sorted.
Insertion Sort
This is like playing a cards. Imaging you have one card at your hand. You are picking a card and placing it exactly at the position.
Merge Sort
Divide and Conquer , More work in combine less work in divide
Quick Sort
More work in divide and less work in conquer
Bubbles
DBMS
Data Modelling
Functional Dependency in RDBMS
A > Atomcity
C > Consistency
I > Isolation
D > Durability
Logical
Physcial
External
DML (Data Manipulation language)
SELECT
INSERT
UPDATE
DELETE
DCL
GRANT
REVOKE
TCL
COMMIT
ROLLBACK
Candidate Key
Super Keys
An unique combination of keys that is useful identify the row