SQL Server Type conversions

1. Cast function

Grammar:

CAST (expression as data_type [(length)])
|       |              |              |
   The maximum length of the data type that the keyword expression or value is to be converted to    

Example:

SELECT CAST (as CHAR (3))

2. Convert function

Grammar:

CONVERT (data_type [(length)], expression [, style])

|             |           |              |           |
   the maximum length expression or value style code of the data type to which the keyword is to be converted     (commonly used on date types)

Example:

SELECT CONVERT (Time, ' 2014-11-30 10:20:29 ')

SQL Server Type conversions