SQLServerPediaSyndication Archives - Technology with Vivek Johari

SQL Triggers – An Introduction

December 8, 2018January 31, 2019 vivekjohari33 Comments

SQL Triggers – An Introduction Contents Introduction Magic Tables Difference between Stored Procedure and Trigger DML Triggers After Triggers Syntax of the After trigger Example of After Trigger for Insert Example of After Trigger for Delete Example of After Trigger for Update Instead of Triggers DDL Triggers DDL Trigger for Create Table DDL Trigger for […]

Isolation levels in SQL Server

August 19, 2012February 1, 2019 vivekjohari33 Comments

Isolation levels :- Isolation level is required to isolate a resource and protect it from other transactions. This is achieved with the help of locks but what locks are needed and how they can be established is decided on the isolation level set on the database level. If low level of Isolation is set, it […]

SQL Server Functions- An Introduction

August 2, 2011February 1, 2019 vivekjohari31 Comments

SQL FUNCTION: – Function in a database can be defined as the code segment consisting of a logical group of SQL statements which takes some input arguments (if required), run in a sequential order and returns the output either in the form of a single value or in the form of a table.Through this article, […]

Sql Joins- Inner Joins, Self Joins, Outer Joins, Cross Joins

January 2, 2010February 1, 2019 vivekjohari33 Comments

I generally feel that people are afraid of Joins in SQL Server. But if they know what the different types of Joins in SQL Server are and how they can be best used then they really enjoy using them. By using the joins we can get data from many tables based on some logical conditions. […]

Difference between Subquery, Nested Subquery and Correlated Subquery

September 29, 2009February 1, 2019 vivekjohari102 Comments

Difference between Subquery, Nested Subquery and Correlated Subquery Query Query can be defined as a way to inquire the data from the database. It is used to extract the data from one table or multiple tables depending upon the user needs. Suppose we have a two tables Student and courses whose structure is given below:- […]

Sql server Constraints – Primary Key, Foreign Key, Unique Key, Not Null, Check Constraints

August 19, 2009February 1, 2019 vivekjohari31 Comments

Introduction A constraint is a property that is assigned to a column or a group of columns to prevent incorrect or corrupt data from entering into the tables. These constraints ensure the accuracy and reliability of the data into the tables. This article will tell about the Sql server Constraints – Primary Key, Foreign Key, […]