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

SQL – Generate decimal numbers sequence for particular number range

-
Image
Friends, Sometimes we need mathematical assistance in SQL for such queries. Same here, it helps me to find challenging in all the way. Some of my friends helps me out to crack the records for my query, Here I am sharing simple solution for this, ;WITH cte      AS (SELECT Cast(-77 AS NUMERIC(22, 3)) AS num –Min value from your data          UNION ALL          SELECT Cast(num + 0.00001 AS NUMERIC(22, 5))          FROM   cte          WHERE  num < Cast(89 AS NUMERIC(22, 5))) — Max value from your data SELECT * FROM   cte OPTION (maxrecursion 0)  Try it 
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 pa...
Read more

Ways to SELECT XML string using Nodes and OPENXML()

-
XML reading is most probably way of reading data from file. Only for knowledge we are checking performance by two ways OPENXML() and Nodes(). Check following the queries at your end as part of "Performace Tuning ". OpenXML() -                       OpenXML() is a rowset provider. OpenXML can be used in T-SQL statements in which rowset providers such as a table, view, or the OPENROWSET function can appear. Example : DECLARE @idoc int , @doc varchar ( 1000 ), @XMLString xml SET @doc = ' <ROOT> <Customer CustomerID="1" ContactName="Nihar"> <Order CustomerID="1" EmployeeID="5" OrderDate="1996-07-04T00:00:00"> <OrderDetail ProductID="11" Quantity="12"/> <OrderDetail ProductID="42" Quantity="10"/> </Order> </Customer> <Customer CustomerID="2" ContactName="HR"> <Order CustomerID=...
Read more