Author Archives: user

SQL – NULL Values Table of content SQL uses the term NULL to represent a non-existent data value in the database. These values are not the same as an empty string or a zero. They don”t hold any space in the database and are used to signify the absence of a value or the unknown […]

SQL – Stored Procedures Table of content SQL Stored Procedures An SQL stored procedure is a group of pre-compiled SQL statements (prepared SQL code) that can be reused by simply calling it whenever needed. It can be used to perform a wide range of database operations such as inserting, updating, or deleting data, generating reports, […]

SQL – Sub Queries Table of content SQL Subqueries An SQL Subquery, is a SELECT query within another query. It is also known as Inner query or Nested query and the query containing it is the outer query. The outer query can contain the SELECT, INSERT, UPDATE, and DELETE statements. We can use the subquery […]