Tag Archives: SQLServerPediaSyndication

SQL Triggers – An Introduction

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 … Continue reading

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Isolation levels in SQL Server

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 … Continue reading

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SQL Server Functions- An Introduction

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 … Continue reading

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

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 … Continue reading

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Difference between Subquery, Nested Subquery and Correlated Subquery

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 … Continue reading

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

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 … Continue reading

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