Skip to main content

MS SQL Server Views

"Creates a virtual table whose contents (columns and rows) are defined by a query. Use this statement to create a view of the data in one or more tables in the database. For example, a view can be used for the following purposes:

- To focus, simplify, and customize the perception each user has of the database.
- As a security mechanism by allowing users to access data through the view, without granting the users permissions to directly access the underlying base tables.
- To provide a backward compatible interface to emulate a table whose schema has changed." [1]

Beside that, our team used view in order to improve the performance of our web apps when a database has a very complicated relationship between its tables by using ORM Frameworks such as Hibernate.

Example code:
--create
CREATE VIEW placeholders
AS
SELECT     EMPKEY AS empkey, CONNUMB AS connumb, EMPNBR AS empNbr, ACEEMPN AS empFirstName, ACEEMPFN AS empLastName, EMPNAM AS empFullName, 
                      EMPSIGN AS empSign, AECSALUT AS empSalutation, AECTITLE AS empTitle
FROM         dbo.HRMAEC

--update
ALTER VIEW placeholders AS
SELECT EMPKEY AS empkey, CONNUMB AS connumb, EMPNBR AS empNbr, ACEEMPN AS empFirstName, ACEEMPFN AS empLastName, EMPNAM AS empFullName1, 
                      EMPSIGN AS empSign, AECSALUT AS empSalutation, AECTITLE AS empTitle,AECEMAIL As empEmail
FROM HRMAEC


-- drop
DROP VIEW placeholders

--select
SELECT * FROM placeholders
WHERE empkey = 1 AND connumb = 1


Reference:
[1]. https://msdn.microsoft.com/en-us/library/ms187956.aspx

Comments

Popular posts from this blog

BIRT - Fix the size of an image

I use a dynamic image as a logo my report in pdf. At the beginning, I use table to align the logo in left or right. I meet a problem with some images with a large width or height. My customer requires that the logo should be displayed in original size. These following steps solves my problem: 1. Use Grid instead of Table 2. Set Grid "Height" is 100%  and "Width" is blank 3. Set "Fit to container" for images are "true". Download the the template here .

[Snippet] CSS - Child element overlap parent

I searched from somewhere and found that a lot of people says a basic concept for implementing this feature looks like below: HTML code: <div id="parent">  <div id="child">  </div> </div> And, CSS: #parent{   position: relative;   overflow:hidden; } #child{   position: absolute;   top: -1;   right: -1px; } However, I had a lot of grand-parents in my case and the above code didn't work. Therefore, I needed an alternative. I presumed that my app uses Boostrap and AngularJs, maybe some CSS from them affects mine. I didn't know exactly the problem, but I believed when all CSS is loaded into my browser, I could completely handle it. www.tom-collinson.com I tried to create an example to investigated this problem by Fiddle . Accidentally, I just changed: position: parent; to position: static; for one of parents -> the problem is solved. Look at my code: <div class="modal-body dn-placeholder-parent-positi...

git cherry-pick [commit]

Customer Needs My team already had a go-live app in a customer environment some months ago. We have been developing some new features for our next milestone. The situation is described in the picture below: We used Git for our codebase management. The go-live app running on our customer environment was at version ` v1 `. The latest sprint release was at version ` v7 ` for our developing app. Our customers wanted to have two separated release packages for our current sprint release. We all know that it was easy to ship the package to the developing app. However, the issue was that how we just picked some features needed for the go-live app. We called this package was a hotfix. Git Cherry-Picking Fortunately, we found that Git provided a way to achieve this task. Actually, we had all commits on the branch ` master ` already. We created a new branch called ` hotfix/v1.1 ` and we traced back which commits needed. We used cherry-picking for merging these commits to this branch....

Selenium - Override javascript functions to ignore downloading process

I have got an issue with downloading process on IE 8. This browser blocks my automatic-download functionality on my app so that I could not work with my test case any more after that. In my case, I didn't care about the file is downloaded or not, I just focus on the result after downloading process finished successfully. Therefore, I found a solution to ignore this process so that I can work normally. I use Primefaces, here is the remote command to trigger the download process <p:remoteCommand name="cmdGenerateDocument" actionListener="#{logic.onGenerateDocument}" update="xrflDocumentCreationPanel" oncomplete="clickDownloadButton();"/> The following is my test case: @Test public void shouldUpdateStep6ToWarningIfStep1IsValidAfterFinished(){ MainPage mainPage = new MainPage(); waitForLoading(mainPage.getDriver()); EmployeeDetailPage empDetailPage = new EmployeeDetailPage(); waitForLoading(empDetailPage.getDriver()); e...

Styling Sort Icons Using Font Awesome for Primefaces' Data Table

So far, Primefaces has used image sprites for displaying the sort icons. This leads to a problem if we want to make a different style for these icons; for example, I would make the icon "arrow up" more blurry at the first time the table loading because I want to highlight the icon "arrow down". I found a way that I can replace these icons with Font Awesome icons. We will use "CSS Pseudo-classes" to achieve it. The hardest thing here is that we should handle displaying icons in different cases. There is a case both "arrow up" and "arrow down" showing and other case is only one of these icons is shown. .ui-sortable-column-icon.ui-icon.ui-icon-carat-2-n-s { background-image: none; margin-left: 5px; font-size: 1.1666em; position: relative; } .ui-sortable-column-icon.ui-icon.ui-icon-carat-2-n-s:not(.ui-icon-triangle-1-s)::before { content: "\f106"; font-family: "FontAwesome"; position: ...