When working with DATE or TIMESTAMP values in Oracle, you'll often need to add or subtract a specific duration, like "90 days" or "4 hours." While you can add days by just date + 90, this becomes clunky for smaller…

The NEXT_DAY function in Oracle SQL is a handy date function that helps you find the date of the next specified day of the week. For example, if it's a Wednesday, you can use NEXT_DAY to find the date of…

The NEW_TIME function in Oracle SQL is a specific-purpose function used to convert a date and time from one time zone to another. Important Note: This is an older Oracle function and only supports a very limited list of time…

The MONTHS_BETWEEN function in Oracle SQL calculates the precise number of months between two dates. This function is essential for any business logic that involves calculating tenure, age, or time differences in months. It's smart enough to return a whole…

The LOCALTIMESTAMP function in Oracle SQL returns the current date and time (including fractional seconds) based on your session's time zone. The most important thing to know about this function is its data type: it returns a TIMESTAMP, which does…

The LAST_DAY function in Oracle SQL is a very convenient datetime function that returns the date of the last day of the month for a given date. It's an essential tool for any kind of financial, billing, or end-of-period reporting…

The FROM_TZ function in Oracle SQL is a straightforward conversion function. Its one and only job is to convert a TIMESTAMP value (which has no time zone information) into a TIMESTAMP WITH TIME ZONE value by "attaching" a time zone…

The FLOOR function in Oracle SQL can be used on numbers, but it also has a version for DATE and TIMESTAMP values. For dates, FLOOR "rounds down" the datetime to the unit you specify. Here is the most important thing…

The EXTRACT function in Oracle SQL is a powerful tool for "pulling out" a single, specific part from a date or timestamp. Want just the YEAR from a DATE? Or the HOUR from a TIMESTAMP? EXTRACT is the function you…

The DBTIMEZONE function in Oracle SQL is a simple function that returns the time zone setting of the database itself. This is different from SESSIONTIMEZONE, which returns the time zone of your current user session. DBTIMEZONE shows the default time…

The CURRENT_TIMESTAMP function in Oracle SQL returns the exact current date, time, and time zone of your SQL session. Its key feature is that it returns a TIMESTAMP WITH TIME ZONE data type. This means the output includes not just…

The CURRENT_DATE function in Oracle SQL is a simple function that returns the current date and time based on your session's time zone. A common point of confusion is its name. Despite being called CURRENT_DATE, the DATE data type in…

The CEIL function in Oracle SQL can be used on numbers, but it also has a powerful version for DATE and TIMESTAMP values. In this context, CEIL "rounds up" a datetime value to the next specified unit of time. This…

Working with dates in SQL can be tricky, especially when you need to add or subtract months. Oracle provides a powerful and straightforward function for this exact task: ADD_MONTHS. This simple tutorial will show you exactly how to use it,…