Category Archives: SQL

HTML Input Attribute

<input> element has many attributes, and each one has a specific meaning. Here we have covered all the major attributes we use in <input> element. Some of the attributes are optional, and some are mandatory to mention. <input> Attributes Type <input type=””> the type attribute defines the input type for the input block. By default, the type value… Read More »

SQL Transaction

If there is a group of SQL commands performed on a database to manipulate the stored data, then all those commands can be treated as a single unit called a transaction. In simple word, we can say that a transaction is a group of SQL queries, and transaction handles all those queries as a single unit. SQL Transaction… Read More »

SQL Injection

Most of the web-applications use SQL database to manage and organize the data of its users and content. Now, most of the websites are dynamic; they all use some kind of SQL relational database management system to fetch and store data. There are many active threats a website can face, and SQL injection is one of those threats.… Read More »

SQL SEQUENCES

In SQL a Sequence is defined as a Database object which is generally used to generate an integer sequence. In Database tables, Sequences often used to populate the numeric primary key column. However, this can also be done using the AUTO_INCREMENT constraint, but Sequences give more flexibility, and here we can define the integer sequence in a different… Read More »

SQL Sub Queries

In SQL if we write a query inside another query, then it would be considered as a nested, inner query, and subquery. Generally, these subqueries applied using the SQL WHERE clause. SQL Sub Queries Subqueries are basically used to set a condition expression, that’s why the subquery executes before the main query. The data sets returned by the… Read More »

SQL Temporary Tables

Some Relational Database Management Systems(RDBMS), support temporary tables. A Temporary Table is similar to the normal tables present in the Database, like the normal table the temporary table support all the SQL commands, the only difference is the temporary table get deleted as soon as the session of the user or table gets ended. SQL Temporary Tables Temporary… Read More »

SQL Having Clause

Like the WHERE clause HAVING clause is used to put a condition on a statement, in SQL we can not use the WHERE statement with aggregated statements such as GROUP BY, so there we use the HAVING clause to set a condition. SQL Having Clause In sort HAVING is a replace of WHERE clause for the GROUP BY… Read More »

SQL Views

A VIEW is an SQL statement which is used to create virtual tables, although it is just a SQL statement like SELECT, UPDATE, etc. but it holds the data like an actual table. VIEWS provide an alternative way to write a complex query, for instance, if there is a complex query you need to use often when you… Read More »