추가 (3)

 

JQuery provides methods to manipulate DOM in efficient way. You do not need to write big code to modify the value of any element's attribute or to extract HTML code from a paragraph or division.

JQuery provides methods such as .attr(), .html(), and .val() which act as getters, retrieving information from DOM elements for later use.

컨텐츠 조작:

The html( ) method gets the html contents (innerHTML) of the first matched element.

Here is the syntax for the method:

selector.html( )

예제:

Following is an example which makes use of .html() and .text(val) methods. Here .html() retrieves HTML content from the object and then .text( val ) method sets value of the object using passed parameter:

<html>
<head>
<title>the title</title>
   <script type="text/javascript" 
   src="/jquery/jquery-1.3.2.min.js"></script>
   <script type="text/javascript" language="javascript">
   
   $(document).ready(function() {

     $("div").click(function () {
      var content = $(this).html();
      $("#result").text( content );
    });

   });

   </script>
   <style>
      #division{ margin:10px;padding:12px;
                 border:2px solid #666;
                 width:60px;
               }
  </style>
</head>
<body>
   <p>Click on the square below:</p>
   <span id="result"> </span>
   <div id="division" style="background-color:blue;">
     This is Blue Square!!
   </div>
</body>
</html>

 

 

DOM 요소 변경

You can replace a complete DOM element with the specified HTML or DOM elements. The replaceWith( content ) method serves this purpose very well.

Here is the syntax for the method:

selector.replaceWith( content )

Here content is what you want to have instead of original element. This could be HTML or simple text.

예제:

Following is an example which would replace division element with "<h1>JQuery is Great</h1>":

<html>
<head>
<title>the title</title>
   <script type="text/javascript" 
   src="/jquery/jquery-1.3.2.min.js"></script>
   <script type="text/javascript" language="javascript">
   
   $(document).ready(function() {

     $("div").click(function () {
       $(this).replaceWith("<h1>JQuery is Great</h1>");
    });

   });

   </script>
   <style>
      #division{ margin:10px;padding:12px;
                 border:2px solid #666;
                 width:60px;
               }
  </style>
</head>
<body>
   <p>Click on the square below:</p>
   <span id="result"> </span>
   <div id="division" style="background-color:blue;">
     This is Blue Square!!
   </div>
</body>
</html>

 

 

DOM 요소 삭제

There may be a situation when you would like to remove one or more DOM elements from the document. JQuery provides two methods to handle the situation.

The empty( ) method remove all child nodes from the set of matched elements where as the method remove( expr ) method removes all matched elements from the DOM.

Here is the syntax for the method:

selector.remove( [ expr ])

or 

selector.empty( )

You can pass optional paramter expr to filter the set of elements to be removed.

예제:

Following is an example where elements are being removed as soon as they are clicked:

<html>
<head>
<title>the title</title>
   <script type="text/javascript" 
   src="/jquery/jquery-1.3.2.min.js"></script>
   <script type="text/javascript" language="javascript">
   
   $(document).ready(function() {

     $("div").click(function () {
       $(this).remove( );
    });

   });

   </script>
   <style>
      .div{ margin:10px;padding:12px;
             border:2px solid #666;
             width:60px;
           }
  </style>
</head>
<body>
   <p>Click on any square below:</p>
   <span id="result"> </span>
   <div class="div" style="background-color:blue;"></div>
   <div class="div" style="background-color:green;"></div>
   <div class="div" style="background-color:red;"></div>
</body>
</html>

 

 

DOM 요소 추가

There may be a situation when you would like to insert new one or more DOM elements in your existing document. JQuery provides various methods to insert elements at various locations.

The after( content ) method insert content after each of the matched elements where as the method before( content ) method inserts content before each of the matched elements.

Here is the syntax for the method:

selector.after( content )

or

selector.before( content )

Here content is what you want to insert. This could be HTML or simple text.

예제:

Following is an example where <div> elements are being inserted just before the clicked element:

<html>
<head>
<title>the title</title>
   <script type="text/javascript" 
   src="/jquery/jquery-1.3.2.min.js"></script>
   <script type="text/javascript" language="javascript">
   
   $(document).ready(function() {

     $("div").click(function () {
       $(this).before('<div class="div"></div>' );
    });

   });

   </script>
   <style>
      .div{ margin:10px;padding:12px;
             border:2px solid #666;
             width:60px;
           }
  </style>
</head>
<body>
   <p>Click on any square below:</p>
   <span id="result"> </span>
   <div class="div" style="background-color:blue;"></div>
   <div class="div" style="background-color:green;"></div>
   <div class="div" style="background-color:red;"></div>
</body>
</html>

 

 

DOM 조작 관련 메소드 목록

 

MethodDescription
after( content )Insert content after each of the matched elements.
append( content )Append content to the inside of every matched element.
appendTo( selector )Append all of the matched elements to another, specified, set of elements.
before( content )Insert content before each of the matched elements.
clone( bool )Clone matched DOM Elements, and all their event handlers, and select the clones.
clone( )Clone matched DOM Elements and select the clones.
empty( )Remove all child nodes from the set of matched elements.
html( val )Set the html contents of every matched element.
html( )Get the html contents (innerHTML) of the first matched element.
insertAfter( selector )Insert all of the matched elements after another, specified, set of elements.
insertBefore( selector )Insert all of the matched elements before another, specified, set of elements.
prepend( content )Prepend content to the inside of every matched element.
prependTo( selector )Prepend all of the matched elements to another, specified, set of elements.
remove( expr )Removes all matched elements from the DOM.
replaceAll( selector )Replaces the elements matched by the specified selector with the matched elements.
replaceWith( content )Replaces all matched elements with the specified HTML or DOM elements.
text( val )Set the text contents of all matched elements.
text( )Get the combined text contents of all matched elements.
wrap( elem )Wrap each matched element with the specified element.
wrap( html )Wrap each matched element with the specified HTML content.
wrapAll( elem )Wrap all the elements in the matched set into a single wrapper element.
wrapAll( html )Wrap all the elements in the matched set into a single wrapper element.
wrapInner( elem )Wrap the inner child contents of each matched element (including text nodes) with a DOM element.
wrapInner( html )Wrap the inner child contents of each matched element (including text nodes) with an HTML structure.

 

 

 

 

Reference : http://www.tutorialspoint.com/jquery/jquery-dom.htm

 

 

 

 

SQL FOREIGN KEY Constraint on ALTER TABLE

- 외래키 추가하기

MySQL / SQL Server / Oracle / MS Access:

ALTER TABLE Orders
ADD FOREIGN KEY (P_Id)
REFERENCES Persons(P_Id)


- 외래키 이름 지정해주기

MySQL / SQL Server / Oracle / MS Access:

ALTER TABLE Orders
ADD CONSTRAINT fk_PerOrders
FOREIGN KEY (P_Id)
REFERENCES Persons(P_Id)


To DROP a FOREIGN KEY Constraint

- 외래키 삭제하기 


MySQL:

ALTER TABLE Orders
DROP FOREIGN KEY fk_PerOrders

SQL Server / Oracle / MS Access:

ALTER TABLE Orders
DROP CONSTRAINT fk_PerOrders


프로젝트를 진행하다 보면 테이블 모델링을 수정해야 할 때가 있다. 이런 저런 추가요구가 들어오면 말이다.

 

그럴 때는 간단하게 SQL 한문장으로 후딱 해치워 버리면 된다.

 

§ 아래는 테이블에 하나의 컬럼을 추가로 만들어 주기위한 SQL문이다.

 

ALTER TABLE table_name ADD column_name datatype

 

§ 테이블에서 필요없는 컬럼을 삭제하려면 아래와 같은 명령어를 사용하면 된다.

 

ALTER TABLE table_name DROP COLUMN column_name

§ 또한 특정 컬럼의 데이타 타입을 변경하려면 아래와 같은 명령어를 사용하면 된다.

Oracle 10G and later: ALTER TABLE table_name MODIFY column_name datatype




§ 오라클이 아닌 다른 데이타베이스 시스템의 경우 아래와 같이 사용하면 된다.

SQL Server / MS Access:

ALTER TABLE table_name ALTER COLUMN column_name datatype

My SQL / Oracle:

ALTER TABLE table_name MODIFY COLUMN column_name datatype