Use of Convert conversion function in SQL

Format:
CONVERT (Data_type,expression[,style])

Description
This style is typically in the time type (Datetime,smalldatetime) and the string type (Nchar,nvarchar,char,varchar)
It is only used when converting to each other.

Example:
SELECT CONVERT (varchar (+), GETDATE (), 101) Now
The result is:
Now
---------------------------------------
|09/15/2001

===================================================================

The style number has the following meanings when converting time:

------------------------------------------------------------------------------------------------------------
Style (2-bit for year) |   Style (4-bit for year) | Input/output format
------------------------------------------------------------------------------------------------------------
0 |   100 | Mon dd yyyy hh:miam (or PM)
------------------------------------------------------------------------------------------------------------
1 |   101 USA | Mm/dd/yy
------------------------------------------------------------------------------------------------------------
2 |   102 ANSI | Yy-mm-dd
------------------------------------------------------------------------------------------------------------
3 |   103 Anglo-French | 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 |   109 | Mon dd yyyy Hh:mi:ss:mmmmAM (or PM)
------------------------------------------------------------------------------------------------------------
10 |   110 USA | Mm-dd-yy
------------------------------------------------------------------------------------------------------------
11 |   111 Japan | Yy/mm/dd
------------------------------------------------------------------------------------------------------------
12 |   ISO | Yymmdd
------------------------------------------------------------------------------------------------------------
13 |   113 Euro Default | DD Mon yyyy hh:mi:ss:mmm (24 hour system)
------------------------------------------------------------------------------------------------------------
14 |   114 | Hh:mi:ss:mmm (24-hour system)
------------------------------------------------------------------------------------------------------------
20 |    ODBC Specification | Yyyy-mm-dd Hh:mi:ss (24-hour system)
------------------------------------------------------------------------------------------------------------
21 |    121 | Yyyy-mm-dd Hh:mi:ss:mmm (24-hour system)
------------------------------------------------------------------------------------------------------------

Statements and Query results:
SELECT CONVERT (varchar), GETDATE (), 0): 2006 10:57am
SELECT CONVERT (varchar), GETDATE (), 1): 05/16/06
SELECT CONVERT (varchar), GETDATE (), 2): 06.05.16
SELECT CONVERT (varchar), GETDATE (), 3): 16/05/06
SELECT CONVERT (varchar), GETDATE (), 4): 16.05.06
SELECT CONVERT (varchar), GETDATE (), 5): 16-05-06
SELECT CONVERT (varchar), GETDATE (), 6): 16 05 06
SELECT CONVERT (varchar), GETDATE (), 7): 05 16, 06
SELECT CONVERT (varchar), GETDATE (), 8): 10:57:46
SELECT CONVERT (varchar), GETDATE (), 9): 2006 10:57:46:827am
SELECT CONVERT (varchar), GETDATE (), 10): 05-16-06
SELECT CONVERT (varchar), GETDATE (), 11): 06/05/16
SELECT CONVERT (varchar), GETDATE (), 12): 060516
SELECT CONVERT (varchar), GETDATE (), 13): 16 05 2006 10:57:46:937
SELECT CONVERT (varchar), GETDATE (), 14): 10:57:46:967
SELECT CONVERT (varchar), GETDATE (), 20): 2006-05-16 10:57:47
SELECT CONVERT (varchar), GETDATE (), 21): 2006-05-16 10:57:47.157
SELECT CONVERT (varchar), GETDATE (): 05/16/06 10:57:47 AM
SELECT CONVERT (varchar), GETDATE (), 23): 2006-05-16
SELECT CONVERT (varchar), GETDATE (), 24): 10:57:47
SELECT CONVERT (varchar), GETDATE (), 25): 2006-05-16 10:57:47.250
SELECT CONVERT (varchar), GETDATE (), (+): 2006 10:57am
SELECT CONVERT (varchar), GETDATE (), 101): 05/16/2006
SELECT CONVERT (varchar), GETDATE (), 102): 2006.05.16
SELECT CONVERT (varchar), GETDATE (), 103): 16/05/2006
SELECT CONVERT (varchar), GETDATE (), 104): 16.05.2006
SELECT CONVERT (varchar), GETDATE (), 105): 16-05-2006
SELECT CONVERT (varchar), GETDATE (), 106): 16 05 2006
SELECT CONVERT (varchar), GETDATE (), 107): 05 16, 2006
SELECT CONVERT (varchar), GETDATE (), 108): 10:57:49
SELECT CONVERT (varchar), GETDATE (), 109): 2006 10:57:49:437am
SELECT CONVERT (varchar), GETDATE (), 110): 05-16-2006
SELECT CONVERT (varchar), GETDATE (), 111): 2006/05/16
SELECT CONVERT (varchar), GETDATE (), 112): 20060516
SELECT CONVERT (varchar), GETDATE (), 113): 16 05 2006 10:57:49:513
SELECT CONVERT (varchar), GETDATE (), 114): 10:57:49:547
SELECT CONVERT (varchar), GETDATE (), 120): 2006-05-16 10:57:49
SELECT CONVERT (varchar), GETDATE (), 121):2006-05-16 10:57:49:000

Original: http://www.cnblogs.com/xionglee/articles/1444916.html

Use of Convert conversion function in SQL