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

How to Use Python Try and Except Logic Correctly

-
In Python, you can avoid exceptions using Try and Except logic. The Error-free programs save a lot of time. Also, you can keep away defects in production.
 

Python tips
How to Use Python Try and Except Logic Correctly


In Python, you can handle un-known errors by using TRY and EXCEPT logic. If the programmer does not take care of this, the default is for Python to print an error message and stops execution. 



So the responsibility of a programmer is upfront he/she has to find errors and handle them correctly. It is possible if you use the TRY and EXCEPT.


Python Syntax for Try and Except.


try:
      c = a/b
except:
      c = 1000000

Try ends with ':' it says that Try block start here. In this block, you can write actual logic. The Except: is another block. That means in this block programmer can specify some value. And that value populates when any error happens.

Try and Except Examples.

Example: 1.

Below is the example to give the expected error in except.

try:
      c = a/b
except ZeroDivisionError:
      c = 1000000


The above example is you can give a name to an error in Except.  When this error happens, it assigns 1000000.


Example: 2.

Below is an example to give anticipated errors.

try:
      c = a/b
except (ValueError, ZeroDivisionError):
      c = 1000000


Also, there can be many except statements associated with a single Try.

Example: 3.

Below is an example to use multiple excepts.

try:
      c = a/b
except ValueError:
    c = 0
except ZeroDivisionError:
      c = 1000000

And, as was mentioned, a variable can hold the value of the error to be caught:

Example: 4.

The below example is to assign a value to the variable when an error happens. 

k = ZeroDivisionError
try:
      c = a/b
except k:
      c = 1000000


If we left out the exception name, it assigns value C for other errors.

try:
      c = a/b
except:
      c = 0


Related Posts.

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