Sql cache dependency, DOT NET Programming

Assignment Help:

How do we enable SQL Cache Dependency?

Below are some of the steps to enable the SQL Cache Dependency:-

  • Enable the notifications for database.
  • Enable the notifications for individual tables.
  • Enable the ASP.NET polling by using the "web.config" file
  • Finally use the Cache dependency object in your ASP.NET code

To enable notifications for the database.

Before you can use SQL Server cache invalidation, you need to enable notifications for the database. This task is done with the aspnet_regsql.exe command-line utility, which is located in the c:\[WinDir]\Microsoft.NET\Framework\[Version] directory.

aspnet_regsql -ed -E -d Northwind

-ed :- command-line switch

-E: - Use trusted connection

-S: - Specify server name it other than the current computer you are working on

-d: - Database Name

So now let's try to understand what happens in the database because of "aspnet_regsql.exe". After we execute the "aspnet_regsql -ed -E -d Northwind" command you will see one new table and four new stored procedures created.

1497_sql cache.png

Figure : - SQL Cache table created for notification

1413_sql cache1.png

Figure : - New stored procedures created

Just to make short run of what the stored procedures do.

"AspNet_SqlCacheRegisterTableStoredProcedure" :- This stored procedure fixed a table to support notifications. This method works by adding a notification trigger to the table, which will fire whenever any row is deleted,inserted , or updated,   .

"AspNet_SqlCacheUnRegisterTableStoredProcedure":- This stored procedure takes a registered table and discard the notification trigger so that notifications won't be created.

"AspNet_SqlCacheUpdateChangeIdStoredProcedure":- The notification trigger calls this stored procedure to update the AspNet_SqlCacheTablesForChangeNotification table, therefore  indicating that the table has modified.

AspNet_SqlCacheQueryRegisteredTablesStoredProcedure :- This extracts just the table names from the AspNet_SqlCacheTablesForChangeNotification table. It is used to get a quick view at all the registered tables.

AspNet_SqlCachePollingStoredProcedure :- This will get  the  complete list of changes from the AspNet_SqlCacheTablesForChangeNotification table. It is used to perform the polling.

Enabling notification for individual tables

When the necessary stored procedure and tables are generated then we have to notify by saying which table needs to be enabled for notifications.

There are 2 ways to achieve this:-

  • aspnet_regsql -et -E -d Northwind -t Products
  • Exec spNet_SqlCacheRegisterTableStoredProcedure 'TableName'

Registering the tables for the notification internally generate trigger for the tables. For instance for a "products" table the following trigger is generated  So any modifications  to the "Products" table will update the "AspNet_SqlCacheNotification' table.

CREATE TRIGGER

dbo.[Products_AspNet_SqlCacheNotification_Trigger] ON

[Products]

FOR INSERT, UPDATE, DELETE

AS BEGIN SET NOCOUNT ON EXEC dbo.AspNet_SqlCacheUpdateChangeIdStoredProcedure

N'Products'

END

The "AspNet_SqlCacheTablesForChangeNotification" contains a single record for each  table you're monitoring. When you make a change in the table (like  inserting, updating, or deleting a record), the change Id column is incremented by one .ASP.NET queries this table continuously keeps track of the most recent changed values for each  table. When this value changes in a subsequent read, ASP.NET knows that the table has changed.

357_sql cache2.png

Figure : - Entries in the Cache notification table


Related Discussions:- Sql cache dependency

3cx pbx sync windows service, Project Description:  You require access t...

Project Description:  You require access to a commercial version of the 3CX PBX system in order to be able to program the API You need sufficient technical knowledge about PB

Main difference between grid layout and flow layout?, What is the main diff...

What is the main difference between Gridlayout and FlowLayout? The Grid Layout provides absolute positioning for the controls placed on the page. The Developers that have their

B.Tech Project:Converting A Hand Drawn Diagram To A neat Dia, The project a...

The project aims at converting a rough hand drawn diagram to a neat diagram. Is it a good project for B.Tech level?Please tell how to go about it??

Inheritance, Assignment for inheritance based on c#

Assignment for inheritance based on c#

I need c# programmer, I need C# Programmer Project Description: To he...

I need C# Programmer Project Description: To help in the production of a C# module to provide a web service. We are based in Littlehampton, West Sussex. Skills required ar

Explain the limitations of ajax, Explain the limitations of AJAX. The f...

Explain the limitations of AJAX. The following are the limitations of AJAX: It is complex to bookmark a particular state of the application. Function given in the code-be

A bot and php command panel, Deat Sir/Madam, I need a small software .NET2...

Deat Sir/Madam, I need a small software .NET2.0 in C# That search for files by - name - extension - part of the name (contains) - file created before a date provided This search

What is xpath, What is XPath? XPath stands for XML Path. It is a langua...

What is XPath? XPath stands for XML Path. It is a language used to access dissimilar parts of an XML document, such as elements and attributes.

Shadowing, What is shadowing? When 2 elements in a program have similar...

What is shadowing? When 2 elements in a program have similar name, one of them can hide and shadow the one. Therefore in such cases the element which shadowed the main element

What is the relationship between a class and an object, What is the relatio...

What is the relationship between a class and an object? A class acts as a blue-print that explains the properties, states, and behaviors that are common to a number of objects.

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd