Data Types in SQL

http://developer.mimer.com/documentation/Mimer_SQL_Reference_Manual/Syntax_Rules4.html

CAST and CONVERT -
http://msdn.microsoft.com/en-us/library/ms191530.aspx


Data types can be converted either implicitly or explicitly:

• Implicit conversions are not visible to the user.
  SQL Server automatically converts the data from one data type to another. For example, when a smallint is compared to an int, the smallint is implicitly converted to int before the comparison proceeds.
• Explicit conversions use the CAST or CONVERT functions.
  The CAST and CONVERT functions convert a value (a local variable, a column, or another expression) from one data type to another. For example, the following CAST function converts the numeric value of $157.27 into a character string of '157.27':
  
  
  

  Copy

  CAST ( $157.27 AS VARCHAR(10) )
  

  Use CAST instead of CONVERT if you want Transact-SQL program code to comply with ISO. Use CONVERT instead of CAST to take advantage of the style functionality in CONVERT.

http://download.oracle.com/docs/cd/B19306_01/appdev.102/b14261/datatypes.htm#i9118

http://www.thesmartcodes.com/how-to-convert-datatypes-in-sql/

DECLARE @firstname AS VARCHAR(30)
DECLARE @lastname AS VARCHAR(30)
DECLARE @LEVEL AS VARCHAR(30)
DECLARE @pay_amount AS DECIMAL(18, 2)
DECLARE @pay_date AS DATETIME
SET @firstname = ‘Subhash’
SET @lastname = ‘Pande’
SET @LEVEL = ‘First’
SET @pay_amount = 1009.30
SET @pay_date = GETDATE()
SELECT @firstname AS First_Name ,
@lastname AS Last_Name ,
@level AS Levels ,
( CONVERT(VARCHAR, @pay_amount) + ‘  ‘ + ‘$’ ) AS Pay_Amount ,
CONVERT(VARCHAR, @pay_date, 106) AS PayDate