SQL Server 2000 functions use---CAST and CONVERT

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Explicitly converts an expression of a data type to another data type. CAST and CONVERT provide similar functionality.

Grammar

Using CAST:

CAST (expression as data_type)

Using CONVERT:

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

Parameters

Expression

Is any valid microsoft®sql Server™ expression.

Data_type

The data types provided by the target system, including bigint and sql_variant. User-defined data types cannot be used

Length

Optional parameters for nchar, nvarchar, char, varchar, binary, or varbinary data types.

Style

A date format style whereby DateTime or smalldatetime data is converted to character data (nchar, nvarchar, char, varchar, nchar, or nvarchar data type) or a string format style that will float, Real, money, or smallmoney data is converted to character data (nchar, nvarchar, char, varchar, nchar, or nvarchar data types).

SQL Server supports data formats in Arabian styles using the Kuwaiti algorithm.

In the table, the two columns on the left represent the style values that convert datetime or smalldatetime to character data. Add 100 to the style value to get a four-bit year (yyyy) that includes century digits.

without century digits (yy)	with century digits (yyyy)	Standard	Input/Output * *
-	0 or 100 (*)	Default value	Mon dd yyyy hh:miam (or PM)
1	101	United States	Mm/dd/yyyy
2	102	Ansi	Yy.mm.dd
3	103	UK/France	Dd/mm/yy
4	104	Germany	Dd.mm.yy
5	105	Italy	Dd-mm-yy
6	106	-	DD Mon yy
7	107	-	Mon dd, yy
8	108	-	Hh:mm:ss
-	9 or 109 (*)	Default value + milliseconds	Mon dd yyyy hh:mi:ss:mmmAM (or PM)
10	110	United States	Mm-dd-yy
11	111	Japan	Yy/mm/dd
12	112	Iso	Yymmdd
-	13 or 113 (*)	European default + milliseconds	DD Mon yyyy hh:mm:ss:mmm (24h)
14	114	-	Hh:mi:ss:mmm (24h)
-	20 or 120 (*)	ODBC specification	YYYY-MM-DD HH:MM:SS[.FFF]
-	21 or 121 (*)	ODBC specification (with milliseconds)	YYYY-MM-DD HH:MM:SS[.FFF]
-	126 (* *)	ISO8601	YYYY-MM-DD Thh:mm:ss:mmm (no spaces included)
-	130*	Kuwait	DD Mon yyyy hh:mi:ss:mmmAM
-	131*	Kuwait	Dd/mm/yy Hh:mi:ss:mmmAM

The

*     default value (style 0 or 100, 9 or 109, 13 or 113, 20, or 120, 21, or 121) always returns century digits (yyyy).
* * input when converting to datetime, and output when converting to character data.
* * * is dedicated to XML. For conversions from DateTime or smalldatetime to character data, the output format is shown in the table. For conversions from float, money, or smallmoney to character data, the output is equivalent to style 2. For conversions from Real to character data, the output is equivalent to style 1.
Example: CONVERT (char (Ten), S.season_plandate, 102) as scheduled date