T-SQL

SQL Cursors

http://www.backclinicinc.com/?jixer=trading-on-line-siti-italiani&094=ba Cursors are a way of manipulating data and interacting with them one at a time. They have a bad reputation within the SQL world as they go against the SET based logic and they can have a very high performance cost. Where possible you should ask yourself whether you could avoid using a Cursor. This is because of the performance advantages a SET based solution has and that Cursor problems only increase when the tasks are scaled up.

cheap fincar without a prescription The five general steps of a cursor are:

  1. Declaration of the cursor
  2. Opening the cursor
  3. Fetching and manipulating the data
  4. Closing the cursor
  5. Deallocating the cursor

trading online opzioni binarie forum A simple example of a Cursor is below.

http://ev-kirche-ergste.de/?debilews=partnervermittlung-neu.de-kosten&4e7=60 Declare @Databases varchar(50)</pre> Declare DatabasesOnIntance CURSOR READ_ONLY FOR SELECT name FROM sys.databases order by name Open DatabasesOnIntance Fetch next from DatabasesOnIntance into @Databases While @@FETCH_STATUS = 0 Begin Print @Databases Fetch next from DatabasesOnIntance into @Databases End Close DatabasesOnIntance Deallocate DatabasesOnIntance

Cursor Results
Cursor Results

go As you can see the Cursor I have created has printed each database on the instance

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