CONVERT function [Data type conversion]

Returns an expression converted to a supplied data type.

This function is similar to the CAST function but allows you to specify a format style to assist with date and time data type conversions. For more information about other conversions, see CAST function [Data type conversion].

Syntax

CONVERT( datatype, expression [ , format-style ] )

Parameters

datatype The data type to which the expression is converted.
expression The expression to be converted.

format-style The style code to apply to the output value. Use this parameter when converting strings to date or time data types, and vice versa. The table below shows the supported style codes, followed by a representation of the output format produced by that style code. The style codes are separated into two columns, depending on whether the century is included in the output format (for example, 06 versus 2006).

Style code 0 is used if an argument is not provided.

Without century (yy) style codes	With century (yyyy) style codes	Output format
-	0 or 100	Mmm dd yyyy hh:nnAA
1	101	mm/dd/yy[yy]
2	102	[yy]yy.mm.dd
3	103	dd/mm/yy[yy]
4	104	dd.mm.yy[yy]
5	105	dd-mm-yy[yy]
6	106	dd Mmm yy[yy]
7	107	Mmm dd, yy[yy]
8	108	hh:nn:ss
-	9 or 109	Mmm dd yyyy hh:nn:ss:sssAA
10	110	mm-dd-yy[yy]
11	111	[yy]yy/mm/dd
12	112	[yy]yymmdd
-	13 or 113	dd Mmm yyyy hh:nn:ss:sss (24 hour clock, Europe default + milliseconds, 4-digit year )
-	14 or 114	hh:nn:ss:sss (24 hour clock)
-	20 or 120	yyyy-mm-dd hh:nn:ss (24-hour clock, ODBC canonical, 4-digit year)
-	21 or 121	yyyy-mm-dd hh:nn:ss.sss (24 hour clock, ODBC canonical with milliseconds, 4-digit year )

Returns

Remarks

The CONVERT function can be used to convert a string to a DATE, TIME, or TIMESTAMP data type, provided that there is no ambiguity when parsing the string. If format-style is specified, the database server may use it as a hint on how to parse the string. The database server returns an error if it cannot parse the string unambiguously.

For information about the styles produced by each output symbol (such as Mmm), see UltraLite date_format creation parameter.

Example

The following statements illustrate the use of format style:

SELECT CONVERT( CHAR( 20 ), OrderDate, 104 ) FROM GROUPO.SalesOrders;

OrderDate
16.03.2000
20.03.2000
23.03.2000
25.03.2000
...

SELECT CONVERT( CHAR( 20 ), OrderDate, 7 ) FROM GROUPO.SalesOrders;

OrderDate
Mar 16, 00
Mar 20, 00
Mar 23, 00
Mar 25, 00
...

The following statement illustrates conversion to an integer and returns the value 5:

SELECT CONVERT( integer, 5.2 );

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