Oracle Diaries: March 2012

Monday, March 26, 2012

SQL Server 2008: Owners vs. Schemas

The other day someone asked me what is dbo, they had trouble differentiating between dbo as object owner and dbo as a schema. That conversation was what inspired this post.

Every object created in SQL Server must have an owner and most of the time the owner is dbo, which is the database owner. One can easily determine the owner of a particular database object by looking at the fully qualified name which is using the following convention:

Server.Database.ObjectOwner.DatabaseObject

Example: Server03.Northwind.dbo.Customers, where dbo is the owner of table Customers that belongs to Northwind database that resides on Server03.

Object gets its owner based on who created the object. By default the user account that creates the object will also own the object and only users in db_owner role can create objects owned by dbo. Someone in db_owner role can create an object owned by any user in the database. Only objects created by members of the sysadmin fixed server role (or by the dbo user) belong to dbo. Objects created by any other user who is not also a member of the sysadmin fixed server role (including members of the db_owner fixed database role):

•Belong to the user creating the object, not dbo.

•Are qualified with the name of the user who created the object.

A schema is a named container for database objects, which allows you to group objects into separate namespaces. It is basically a way to logically group objects such as tables, views, stored procedures etc.
You can assign a user login permissions to a single schema so that the user can only access the objects they are authorized to access. Schemas can be created and altered in a database, and users can be granted access to a schema. A schema can be owned by any user, and schema ownership is transferable.
The dbo schema is the default schema for a newly created database. The dbo schema is owned by the dbo user account. By default, users created with the CREATE USER Transact-SQL command have dbo as their default schema.

Users who are assigned the dbo schema do not inherit the permissions of the dbo user account. No permissions are inherited from a schema by users; schema permissions are inherited by the database objects contained in the schema.

Before SQL Server 2005, schemas used to be equivalent to database users. Now each schema is a distinct namespace that exists independently of the user who created it. It can be owned by any user and its ownership is transferable.

Thursday, March 8, 2012

Show and hide paragraphs using JQuery

Below is the JQuery code I used to show and hide paragraphs when user clicks on the hyperlink - paragraph title:

<!DOCTYPE html>
<html lang="en">
<head>
 <meta charset="UTF-8" />
     <title>Test
 <script type="text/javascript" src="js/jquery.js"></script>
 <script type="text/javascript">
  $(document).ready(function(){  
   $('p').hide();
   
   //toggle the componenet with class msg_body  
   $('a.title').click(function()  {  
    var res = this.id.substr(1); 
   $('#p' + res).slideToggle(500);

   });
  });
 </script>  
</head>
<body>

   <a href="#" class="title" id="t1">Topic 1</a>
 <p id="p1">Testing 1
  </p>

 

  <a href="#" class="title" id="t2">Topic 2</a>
 <p id="p2">Testing 2

 

 

  <a href="#" class="title" id="t3">Topic 3</a>
 <p id="p3">Testing 3

 </p>

 

  <a href="#" class="title" id="t4">Topic 4</a>
 <p id="p4">Testing 4

</body>
</html>

Tuesday, March 6, 2012

7 CSS3 properties one must know

border-radius with that one you can create rounded corners

-webkit-border-radius: 4px;   
-moz-border-radius: 4px;   
border-radius: 4px;

and even circles:

-moz-border-radius: 50px;
-webkit-border-radius: 50px;
 border-radius: 50px;

box-shadow allows you to immediately apply depth to your elements

-webkit-box-shadow: 1px 1px 3px #292929;
-moz-box-shadow: 1px 1px 3px #292929;
box-shadow: 1px 1px 3px #292929;

-webkit-box-shadow: 1px 1px 3px green, -1px -1px blue;
-moz-box-shadow: 1px 1px 3px green,-1px -1px blue;
box-shadow: 1px 1px 3px green, -1px -1px blue;

box-shadow accepts four parameters: x-offset y-offset blur color of shadow

text-shadow same as box-shadow but applied to text
```
.box {
background: url(image/path.jpg) 0 0 no-repeat,
 url(image2/path.jpg) 100% 0 no-repeat;
}
```
In the case above, first background is placed in the top left position (0 0) and second - the top right position (100% 0)

background-size

background: url(path/to/image.jpg) no-repeat;
 -moz-background-size: 100% 100%;
 -o-background-size: 100% 100%;
 -webkit-background-size: 100% 100%;
 background-size: 100% 100%;

text-overflow text-overflow property can accept two values:
- clip
- ellipsis
This property can be used to cut off text that exceeds its container, while still providing a bit of feedback for the user, like an ellipsis.
```
.box {
   -o-text-overflow: ellipsis;
   text-overflow:ellipsis;

   overflow:hidden;
   white-space:nowrap;

   border: 1px solid black;
   width: 400px;
   padding: 20px;

   cursor: pointer;
}
```
Resize allows us to specify how a textarea is resized. Possible values: both: Resize vertically and horizontally horizontal: Limit resizing to horizontally vertical: Limit resizing to vertically none: Disable resizing
```
textarea {   
   -moz-resize: vertical;   
   -webkit-resize: vertical;   
   resize: vertical;   
}  
```