When using the TO_CHAR() function to format a datetime value in Oracle Database, you can add the meridiem indicator (AM/PM) by simply adding either AM or PM to your format model.
Oracle then displays the appropriate meridiem indicator, depending on whether the time value is AM or PM.
You can provide it in any uppercase or lowercase, and with or without dots (e.g. AM, A.M. am, a.m, etc). Oracle will then display the meridiem indicator as specified.
Below are 5 functions that enable you to return the week number from a date in MariaDB. Four return just the week, and one returns both the week and year combined.
Below are two functions that can be used to extract the month from a date in Oracle Database.
When using the TO_CHAR(datetime) function in Oracle Database, you can use the Q format element to return the quarter that a given date belongs to.
With Oracle Database, we can use the TO_CHAR(datetime) function to return a datetime value, formatted in a way that we specify.
We can use this function to return the day name from a date (as well as any other parts of the datetime value).
In MariaDB, you can use the TIMESTAMPDIFF() function to calculate a person’s age (or the age of anything for that matter).
TIMESTAMPDIFF() is a built-in date and time function that returns the difference between two date or datetime expressions. Passing YEAR as the first argument, date of birth as the second argument, and the current date as the third, will return the age in years.
Below are two functions that can be used to return the day from a date in Oracle Database.
Below are two functions that can be used to extract the year from a date in Oracle Database.
When working with functions that return dates, Oracle Database returns these dates based on the value of the NLS_DATE_FORMAT parameter.
There is also an NLS_TIMESTAMP_FORMAT parameter and an NLS_TIMESTAMP_TZ_FORMAT parameter, both of which have a datetime format mask that can be specified separately.
All of these parameters have their default values derived from the NLS_TERRITORY parameter (which by default, is operating system-dependent).
When working with functions that return dates, Oracle Database returns these dates based on the value of the NLS_DATE_FORMAT parameter.
There is also an NLS_TIMESTAMP_FORMAT parameter and an NLS_TIMESTAMP_TZ_FORMAT parameter, both of which have a datetime format mask that can be specified separately.
All of these parameters have their default values derived from the NLS_TERRITORY parameter (which by default, is operating system-dependent).
So, to change the date format for your session, you can either update the NLS_TERRITORY parameter, or explicitly update each parameter individually.
This article provides examples of checking and changing these values, and viewing the results.