CAST and CONVERT (T-SQL) Explicitly converts an expression of one data type to another. CAST and CONVERT provide similar functionality.Syntax Using CAST:CAST(expression AS data_type)Using CONVERT:CONVERT (data_type[(length)], expression [, style])Arguments expression Is any valid Microsoft® SQL Server™ expression. For more information, see Expressions. data_type Is the target system-supplied data type. User-defined data types cannot be used. For more information about available data types, see Data Types. length Is an optional parameter of nchar, nvarchar, char, varchar, binary, or varbinary data types. style Is the style of date format you want when converting datetime or smalldatetime data to character data (nchar, nvarchar, char, varchar, nchar, or nvarchar data types), or the string format when converting float, real, money, or smallmoney data to character data (nchar, nvarchar, char, varchar, nchar, or nvarchar data types). In the table, the two columns on the left represent the style values for datetime or smalldatetime conversion to character data. Add 100 to a style value to get a four-place year that includes the century (yyyy). Without century (yy) With century (yyyy) Standard Input/Output** - 0 or 100 (*) Default mon dd yyyy hh:miAM (or PM) 1 101 USA mm/dd/yy 2 102 ANSI yy.mm.dd 3 103 British/French dd/mm/yy 4 104 German dd.mm.yy 5 105 Italian dd-mm-yy 6 106 - dd mon yy 7 107 - mon dd, yy 8 108 - hh:mm:ss - 9 or 109 (*) Default + milliseconds mon dd yyyy hh:mi:ss:mmmAM (or PM) 10 110 USA mm-dd-yy 11 111 JAPAN yy/mm/dd 12 112 ISO yymmdd - 13 or 113 (*) Europe default + milliseconds dd mon yyyy hh:mm:ss:mmm(24h) 14 114 - hh:mi:ss:mmm(24h) - 20 or 120 (*) ODBC canonical yyyy-mm-dd hh:mi:ss(24h) - 21 or 121 (*) ODBC canonical (with milliseconds) yyyy-mm-dd hh:mi:ss.mmm(24h) * The default values (style 0 or 100, 9 or 109, 13 or 113, 20 or 120, and 21 or 121) always return the century (yyyy). ** Input when converting to datetime; Output when converting to character data.
Explicitly converts an expression of one data type to another. CAST and CONVERT provide similar functionality.Syntax
Using CAST:CAST(expression AS data_type)Using CONVERT:CONVERT (data_type[(length)], expression [, style])Arguments
expression
Is any valid Microsoft® SQL Server™ expression. For more information, see Expressions.
data_type
Is the target system-supplied data type. User-defined data types cannot be used. For more information about available data types, see Data Types.
length
Is an optional parameter of nchar, nvarchar, char, varchar, binary, or varbinary data types.
style
Is the style of date format you want when converting datetime or smalldatetime data to character data (nchar, nvarchar, char, varchar, nchar, or nvarchar data types), or the string format when converting float, real, money, or smallmoney data to character data (nchar, nvarchar, char, varchar, nchar, or nvarchar data types).
In the table, the two columns on the left represent the style values for datetime or smalldatetime conversion to character data. Add 100 to a style value to get a four-place year that includes the century (yyyy). Without
century
(yy) With
century
(yyyy) Standard Input/Output**
- 0 or 100 (*) Default mon dd yyyy hh:miAM (or PM)
1 101 USA mm/dd/yy
2 102 ANSI yy.mm.dd
3 103 British/French dd/mm/yy
4 104 German dd.mm.yy
5 105 Italian dd-mm-yy
6 106 - dd mon yy
7 107 - mon dd, yy
8 108 - hh:mm:ss
- 9 or 109 (*) Default + milliseconds mon dd yyyy hh:mi:ss:mmmAM (or PM)
10 110 USA mm-dd-yy
11 111 JAPAN yy/mm/dd
12 112 ISO yymmdd
- 13 or 113 (*) Europe default + milliseconds dd mon yyyy hh:mm:ss:mmm(24h)
14 114 - hh:mi:ss:mmm(24h)
- 20 or 120 (*) ODBC canonical yyyy-mm-dd hh:mi:ss(24h)
- 21 or 121 (*) ODBC canonical (with milliseconds) yyyy-mm-dd hh:mi:ss.mmm(24h)
* The default values (style 0 or 100, 9 or 109, 13 or 113, 20 or 120, and 21 or 121) always return the century (yyyy).
** Input when converting to datetime; Output when converting to character data.