Featured Post

SQL Interview Success: Unlocking the Top 5 Frequently Asked Queries

-
Image
 Here are the five top commonly asked SQL queries in the interviews. These you can expect in Data Analyst, or, Data Engineer interviews. Top SQL Queries for Interviews 01. Joins The commonly asked question pertains to providing two tables, determining the number of rows that will return on various join types, and the resultant. Table1 -------- id ---- 1 1 2 3 Table2 -------- id ---- 1 3 1 NULL Output ------- Inner join --------------- 5 rows will return The result will be: =============== 1  1 1   1 1   1 1    1 3    3 02. Substring and Concat Here, we need to write an SQL query to make the upper case of the first letter and the small case of the remaining letter. Table1 ------ ename ===== raJu venKat kRIshna Solution: ========== SELECT CONCAT(UPPER(SUBSTRING(name, 1, 1)), LOWER(SUBSTRING(name, 2))) AS capitalized_name FROM Table1; 03. Case statement SQL Query ========= SELECT Code1, Code2,      CASE         WHEN Code1 = 'A' AND Code2 = 'AA' THEN "A" | "A
Post a Comment

Everything You Need To Know About Amazon Machine Image

-
Essentially a virtual machine image or snapshot ”An Amazon Machine Image (AMI) is a special type of pre-configured operating system and virtual application software which is used to create a virtual machine within the Amazon Elastic Compute Cloud (EC2).
Amazon machine image

It serves as the basic unit of deployment for services delivered using EC2.” AWS supports the following virtual image types for import/export: VMware ESX VMDK images, VMware ESX OVA (export only), Citrix Xen VHD images and Microsoft Hyper-V VHD images.

Life Cycle of AMI

AMI cycle
The above diagram summarizes the AMI lifecycle. After you create and register an AMI, you can use it to launch new instances. (You can also launch instances from an AMI if the AMI owner grants you launch permissions.) You can copy an AMI to the same region or to different regions. When you are finished launching an instance from an AMI, you can deregister the AMI.

Comments

Post a Comment

Thanks for your message. We will get back you.

Popular posts from this blog

How to Fix datetime Import Error in Python Quickly

-
Image
Here's a quick resolution for import datetime Python error . The reason is your .py python script name and datetime  are the same. I'll show you how this error happens and its resolution.   Here's the Resolution for ImportError I've created a script called 'datetime.py.' to check whether the minute value is 'odd' or not. During the import of my python script, I got the import error cannot import name datetime. My Script: datetime.py My script's intention is to find whether the minute value is odd or not. Python Logic from datetime import datetime odds = [ 1 , 3 , 5 , 7 , 9 , 11 , 13 , 15 , 17 , 19 , 21 , 23 , 25 , 27 , 29 , 31 , 33 , 35 , 37 , 39 , 41 , 43 , 45 , 47 , 49 , 51 , 53 , 55 , 57 , 59 ] right_this_minute = datetime.today().minute if right_this_minute in odds: print ( "This minute seems a little odd." ) else : print ( "Not an odd minute." ) ImportError I have imported my datetime.py from Linux. It gives an error
Read more

Explained Ideal Structure of Python Class

-
Image
When you are designing a class, you need to ensure that the classification of its critical parts is outlined at the beginning. The clearer the initial design, the more performant and scalable the class is. Some of the components in the order in which they should be defined in the class are mentioned as follows. Ideal structure of a class Class variables Constants or default variables are usually defined at the top of the class. For someone who is reading the code, it comes as an easy-to-view consolidated list, and for the interpreter it ensures that all such variables are processed before diving into the main logic of the class, including any other Instance method or constructor. The __init__ method The __init__ method provides information about inputs needed and how to instantiate the class. It is also the constructor of the class, which the very first method called while initializing the class . Special Python methods These methods change the functionality of the class or provide add
Read more

How to Check Kafka Available Brokers

-
Image
Here's the command to check the list of brokers present in a Kafka Cluster. You can say the Broker is the heart of the Kafka cluster. In simple terms, it works as a process. The main function is to receive messages from publishers and gives permission to access messages by consumers. How to Check Available Brokers in Kafka Here is the command: linux$  ./zookeeper-shell.sh zookeeper-IPaddress:2181 | "ls /brokers/ids" Just use the above command to get the number of brokers present in your host (Kafka Cluster). What is Default Broker-id in Kafka  The default broker id is -1 . When you create a new broker, it adds to -1. Then, it gives a new broker id. The broker ids will be generated from  reserved.broker.max.id + 1. Types of broker ids. Use assigned Zookeeper generated broker id. According to Wiki: Kafka runs on a cluster of one or more servers (called brokers), and the partitions of all topics are distributed across the cluster nodes.  Additionally, partitions are replicat
Read more