## What is a leaf node in SQL?

In Sql Server an index is made up of a set of pages (index nodes) that are organized in a B+ tree structure. This structure is hierarchical in nature. The top node is called the ROOT node (Root Page). The bottom level of nodes in the index are called the leaf nodes (leaf Pages).

### What is a leaf node in a tree?

Leaf. In a tree data structure, the node which does not have a child is called as LEAF Node. In simple words, a leaf is a node with no child. In a tree data structure, the leaf nodes are also called as External Nodes. External node is also a node with no child.

**How do you calculate leaf nodes in a tree?**

An iterative algorithm to get the total number of leaf nodes of binary tree

- if the root is null then return zero.
- start the count with zero.
- push the root into Stack.
- loop until Stack is not empty.
- pop the last node and push the left and right children of the last node if they are not null.

**How do you check if a node is a leaf in a binary tree?**

Approach: Store the degree of all the vertices in an array degree[]. For each edge from A to B, degree[A] and degree[B] are incremented by 1. Now every node which not a root node and it has a degree of 1 is a leaf node and all the other nodes are not.

## Does SQL Server use B+ tree?

B+Trees in SQL Server SQL Server stores its indexes in B+Tree format. There are a few exceptions – for example temporary hash indexes, created during a hash join operation, or column store indexes, which are not really indexes at all.

### What is node in tree data structure?

A tree data structure is a non-linear data structure because it does not store in a sequential manner. It is a hierarchical structure as elements in a Tree are arranged in multiple levels. In the Tree data structure, the topmost node is known as a root node. Each node contains some data, and data can be of any type.

**What is node in data structure?**

A node is a basic unit of a data structure, such as a linked list or tree data structure. Nodes contain data and also may link to other nodes. Links between nodes are often implemented by pointers.

**How do I find my leaf node?**

Steps to find all leaf nodes in a binary tree in Java

- If give tree node or root is null then return.
- print the node if both right and left tree is null, that’s your leaf node.
- repeat the process with both left and right subtree.

## How do you count nodes?

Count the number of nodes in a given binary tree

- Do postorder traversal.
- If the root is null return 0. (base case all well for the recursion)
- if the root is not null then make a recursive call to the left child and right child and add the result of these with 1 ( 1 for counting the root) and return.

### How do I know if a node is a leaf node?

The logic to check if a node is a leaf or not is simple, if both left and right children of that node are null then it’s a leaf node. This logic is encapsulated in the isLeaf() method of the TreeNode class.

**How do you count nodes in a binary tree?**

Find the left and the right height of the given Tree for the current root value and if it is equal then return the value of (2height – 1) as the resultant count of nodes. Otherwise, recursively call for the function for the left and right sub-trees and return the sum of them + 1 as the resultant count of nodes.