Cursor in SQL Server

Cursor in SQL Server is a control structure which process data row by row. It enables rows in a result to process sequentially. SQL Cursor is a type of iterator which can be used to process any record of table & can modify records according to our needs.

To use cursors in SQL procedures, you need to do the following:

  • Declare a cursor that defines a result set.
  • Open the cursor to establish the result set.
  • Fetch the data into local variables as needed from the cursor, one row at a time.
  • Close and de-allocate the cursor when done.

For simple example of SQL Cursor, I used below example. I used table that I used in earlier post Delete Duplicate Rows in SQL.

In above example, I simple select column EMail of user table. I assign is to @EMailId variable. Then  Printing current row of SQL cursor one by one.!

ursor-example-in-SQL-server

SQL Cursor processes records one by one, so it consumes lots of memory & time. So use of cursor should be minimal.!

How to Delete Duplicate Rows in SQL Server

User-Table-with-sample-data In earlier post, I published article about Find duplicate rows in SQL. Now It’s easy when you have small amount of duplicate data. But in million records,it’s very difficult to delete duplicate rows in SQL. Continue with older post, I have added one more duplicate Email.My table will look like below.! Now what I want is, […] Continue Reading →

SQL Order by string And Number

order-by-string-and-number Order By clause is used to order a number or string of any column of SQL. We can esaily order any column if it;s data-type is INTEGER.Suppose we have column contain data like 2A,1,4,3B,11,111 in VARCHAR column and need to order this column.So below SQL tutorial is about Order by String and number in SQL […] Continue Reading →

How to block IP Address from website

block-IP-address Many times we want to block IP Address so particular machine is not able to access website/blog again. People may be hackers,enemies,Invalid clickers or may be another.Below is guide to block IP address from website. Login to Cpanel Account Almost all Hosting providers offers you cPanel.Login to your cPanel,for my example I use BlueHost here. Go to […] Continue Reading →

Date Functions in SQL Server with Examples

Date-functions-in-SQL-server As a good programmer,you need to use many Date functions in SQL Server.I share here most used Date functions of SQL Server which will do different functionality according to its needs. GETDATE() You can easily retrieve current Date Time in SQL Server using GETDATE() function. Query : select GETDATE() CONVERT() Many times,We want to convert Date Format […] Continue Reading →

How to write- create Stored Procedure in SQL Server

A stored procedure is a group of Transact-SQL statements compiled into a single execution plan.(Source: MSDN).To create stored procedure in SQL Server,Go to Database ->Programmability->Stored Procedures.Click right click and click on New Stored Procedure.It will create a new Query Window for you. You will get above image script in your SQL Server.In this script,you have to […] Continue Reading →

Get comma separated values in SQL Server

comma-separated-values-in-SQL-server Many times,We want to covert rows of SQL table into comma separated string which works as value.You can get comma separated values in SQL Server using COALESCE function or without it. I hope you have created table,otherwise in my example check Case Statement in SQL Server for to create & insert scripts for Product Table. After creating Product […] Continue Reading →

Case Statement in SQL

Case-Statement -in-SQL Case When statement in SQL server is very much similar like switch case statement in C.Below is  SQL Case When statement syntax. Simple CASE statement in SQL To understand Case expression in SQL,here is example of Case statement .First of I create table of product.It contains ProductId(Auto increment,Primary key),ProductName,Price,Availability columns. You can use below script […] Continue Reading →