ORA-1843: not a valid month while updating record

Question

I want to update my date column for some purpose. The value already stored in the column is like below

18-06-14

and while updating If I don\'t updat

Answer 1

A date does not have a format - it is stored internally to the database as 7-bytes (representing year, month, day, hour, minute and second) and it is not until whatever user interface you are using (i.e. SQL/Plus, SQL Developer, Java, etc) tries to display it to you, the user, and converts it into something you would find meaningful (usually a string) that the date has a format.

If you are providing a formatted date to a procedure then it will be a string and Oracle will try to implicitly cast it to a date using the NLS_DATE_FORMAT session parameter:

UPDATE your_table
SET your_date_column = '18-06-14'; -- or equivalently via a bind parameter

Is implicitly converted to

UPDATE your_table
SET your_date_column = TO_DATE(
                         '18-06-14',
                         ( SELECT value
                           FROM   NLS_SESSION_PARAMETERS
                           WHERE  parameter = 'NLS_DATE_FORMAT' )
                       );

If the NLS_DATE_FORMAT does not match then Oracle will raise an exception (and the parameter can be set by each user so you should not rely on it being consistent - especially in international organisations when the default date format depends on your territory and language).

If you are updating the value then use a DATE literal and not a string:

UPDATE your_table
SET your_date_column = DATE '2014-06-18';

Or explicitly convert the string and provide the format model:

UPDATE your_table
SET your_date_column = TO_DATE( '18-06-14', 'DD-MM-RR' );

The same is true for passing parameters to your function. Either use a DATE literal:

BEGIN
  your_procedure(
    p_launch_date => DATE '2014-06-18'
  );
END;
/

or explicitly convert the string to a date (and do not rely on implicit conversion):

BEGIN
  your_procedure(
    p_launch_date => TO_DATE( '18-06-14', 'DD-MM-RR' )
  );
END;
/