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Indexes in Databases: What They Are and Why They Matter

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If you've ever worked with databases, you've likely heard the term "index" before. But what exactly are indexes, and why are they important? In this blog post, we'll explore the basics of indexes in databases and why they matter. What is an Index? An index is a data structure that is used to improve the speed of database queries. When you perform a query on a database, the database must search through all of the rows in the table to find the data you're looking for. This can be slow and inefficient, especially if the table is very large. Indexes provide a way to speed up this process. An index is essentially a list of pointers that point to the locations of data in the table. When you perform a query on the database, the database can use the index to quickly find the data you're looking for, rather than searching through all of the rows in the table. Why Are Indexes Important? Indexes are important for several reasons. First and foremost, they can signific

Database Normalization

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Here we will discuss four types  of Normalization and some important concepts like candidate keys , Prime & Non-Prime attributes Database Normalization is a technique to remove or reduce redundancy from the tables in the database.  Types of Redundancy There are two types of redundancies that can occur in database tables. Row Level Redundancy In this type of redundancy, there is a repetition of the same row in the same table. For example, a table name as 'STUDENT' in which data of students is entered, if we enter the same student's data multiple time then, in this case, Row Level redundancy occurs as shown below: In the above case, there is a repetition of a student data whose name is 'Haider', this is what we called row-level redundancy. The solution of Row Level Redundandancy This Row-level Redundancy can be corrected by setting a primary column in the table. In this case, we set SID as the primary key column ( such column must contain unique & not null

Database Management System VS SQL

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To run any computer application, Database is the most essential. And for this, one must have a clear idea about the difference between DBMS software and SQL tool . In this article, you’ll be better able to understand this important aspect. First of all, what is actually a Database also known as DB ? The answer is, Database is a collection of data which allows the storage & manipulation of data. The reason we prefer a database over storing data in a random text file is actually the better management system. To manage large data, there is a need for a proper system, as per the requirement of the application. Such a system is called Database Management System.   On the other hand, Structured Query Language   is a Programming Language basically used to access the DB. Structured Query Language is such a command; you write to manipulate data. It is the most popular programming language for the  Database Management Systems to date. Therefore, in a linear structure, first comes the DB ,

MS SQL SERVER & MYSQL SELECT database with DISTINCT, WHERE & ORDER BY Clause

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The  SELECT  statement in  SQL  syntax is used to retrieve data from the tables that exist in the database that we want to retrieve. Displays this result in tabular format. Syntax: SELECT  column_name  FROM  table_name; The  semicolon  is used at the end of the query just to show that our query is completed, for example, If you write two or more select queries than each query is separated by a semicolon. And  FROM  is used to connect to the respective table we want to deal with.  The syntax of MS SQL SERVER and MYSQL SELECT database is the same. Demo DataBase: Here is a demo database tables to help you better understand. Here are the Structured Query Language queries to create your own tables just like this table. Just copy it and paste it in your SQL server or MySQL workbench and start practising on MS SQL SERVER or MYSQL SELECT database with DISTINCT, WHERE & ORDER BY Clause. 1ST: CREATE TABLE DPT ( DPTNO INT , DNAME VARCHAR (30), DptLoc VARCHAR (20)); INSERT INTO DPT VAL

What is Sql

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Here we learn about important aspects of the structured query language, its importance, its use, and its  relation with databases.     SQL is a domain-specific language used in programming and to handle data in a database management system . In simple words, it is used to communicate with databases. Writing and executing the way you render data from the database is called a query. The code you use to write the queries is a structured query language. What is meant by domain-specific?  Here is a quick definition to help you understand domain-specific languages, but first you need to understand what a general-purpose language or GPL is, these are programming dialects that can be used to tackle a wide variety of problems using one of these languages. e.g C++, C#, Java, Ruby, Python, Rust. domain-specific languages or DSL for short are created to work on a known problem they are often created within an organization that wants a way to define their solutions using a syntax that more closel