TO_TIMESTAMP
Syntax
Purpose
TO_TIMESTAMP
converts char
to a value of TIMESTAMP
data type.
For char
, you can specify any expression that evaluates to a character string of CHAR
, VARCHAR2
, NCHAR
, or NVARCHAR2
data type.
The optional DEFAULT
return_value
ON
CONVERSION
ERROR
clause allows you to specify the value this function returns if an error occurs while converting char
to TIMESTAMP
. This clause has no effect if an error occurs while evaluating char
. The return_value
can be an expression or a bind variable, and it must evaluate to a character string of CHAR
, VARCHAR2
, NCHAR
, or NVARCHAR2
data type, or null. The function converts return_value
to TIMESTAMP
using the same method it uses to convert char
to TIMESTAMP
. If return_value
cannot be converted to TIMESTAMP
, then the function returns an error.
The optional fmt
specifies the format of char
. If you omit fmt
, then char
must be in the default format of the TIMESTAMP
data type, which is determined by the NLS_TIMESTAMP_FORMAT
initialization parameter. The optional 'nlsparam'
argument has the same purpose in this function as in the TO_CHAR
function for date conversion.
This function does not support CLOB
data directly. However, CLOB
s can be passed in as arguments through implicit data conversion.
See Also:
"Data Type Comparison Rules" for more information.
Examples
The following example converts a character string to a timestamp. The character string is not in the default TIMESTAMP
format, so the format mask must be specified:
SELECT TO_TIMESTAMP ('10-Sep-02 14:10:10.123000', 'DD-Mon-RR HH24:MI:SS.FF') FROM DUAL; TO_TIMESTAMP('10-SEP-0214:10:10.123000','DD-MON-RRHH24:MI:SS.FF') --------------------------------------------------------------------------- 10-SEP-02 02.10.10.123000000 PM
The following example returns the default value of NULL because the specified expression cannot be converted to a TIMESTAMP
value, due to an invalid month specification:
SELECT TO_TIMESTAMP ('10-Sept-02 14:10:10.123000' DEFAULT NULL ON CONVERSION ERROR, 'DD-Mon-RR HH24:MI:SS.FF', 'NLS_DATE_LANGUAGE = American') "Value" FROM DUAL;
See Also:
NLS_TIMESTAMP_FORMAT
initialization parameter for information on the default TIMESTAMP
format and "Datetime Format Models" for information on specifying the format mask