ALTER TABLE STATEMENTS

-

SQL ALTER TABLE Syntax

Add a column in a table, use the following syntax:

        ALTER TABLE table_name
        ADD column_name datatype
 
Delete a column in a table, use the following syntax (notice that some database systems don't allow deleting a column):

        ALTER TABLE table_name
        DROP COLUMN column_name
 
Change the data type of a column in a table, use the following syntax:

1) My SQL / SQL Server / MS Access:

ALTER TABLE table_name
ALTER COLUMN column_name datatype
 
2) Oracle:

ALTER TABLE table_name
MODIFY column_name datatype
 
 
You can try it... 
Hopes it will helps you

Comments

Post a Comment

Popular posts from this blog

Add Serial no in crystal report without coding

-
Image
Adding a serial number in grouping without any code. I have placed the step by step screenshots which will explain easily how to do it.   1) Add a new field in Running Total Fields in Field Explorer   Give a proper name to your Running total name. For example I have choosen here RTotal0. Now categorize based on which field in database you want to summarize it. Next is as we want serial number select count. If you want your serial number to start again from the start when the value in the group changes then select on change of group and specify the grouping name else keep the default value.   Smaple Preview of the Design View of Report where I Have added SRNo column at the start in grouping section.  
Read more

File operations in C# (.net)

-
Here we are performing some basic file operations which widely needed in applications. ASPX :     <div>         <asp:Button ID="Button1" runat="server" Text="CLick" onclick="Button1_Click" />         <asp:FileUpload ID="FileUpload1" runat="server" /><br /><br />          </div> C# :        using System.IO;        using System.Text;         protected void Button1_Click(object sender, EventArgs e)         {             string path = @"E:\MVC Application Demos\ABC.txt";            // File Path taken             string name = FileUpload1.FileName.ToString();                // Here we get File Name only             string path1 = FileUpload1.PostedFile.FileName.ToString();    // Here we get File Path only             if (File.Exists(path.ToString()))             {                      //     ClientScript.RegisterStartupScript(this.GetType(), "myalert"
Read more

Working with Oracle's BLOB and Microsoft's C#

-
We used this title for describing technologies , we are working in. Here we will see "  How to store files in oracle database using c# ?   " Step 1:           Use file uploader controller to browse directories. Step 2:          Before uploading file or its path , we need to understand BLOB of Oracle          BLOB  ( Binary Large Objects ) :                                                    File content store in binary format.In Oracle , BLOB and    CLOB  (Character Large Object) used.Technically BLOB prefered.For more info regarding BLOB click here  . Step 3 :        In C# , use System.IO namespace for file operations.     Step 4:         string path = FileUpload1.PostedFile.FileName.ToString();         string FileName = FileUpload1.FileName.ToString();         string FileSize = FileUpload1.PostedFile.ContentLength.ToString();         string FileContent = FileUpload1.PostedFile.ContentType.ToString();         string filename = Path.GetFileName(path
Read more