Database Management Systems
MariaDB includes many functions that allow you to return time and datetime values in a variety of formats.
Two functions allow you to format the time portion using a 12 hour clock, with the AM/PM designator are DATE_FORMAT() and TIME_FORMAT().
There are many format specifiers that can be used with these functions, but only a couple that return the AM/PM designator.
Continue readingIn MariaDB, JSON_ARRAY() is a built-in function that returns a JSON array containing the specified values, provided as arguments.
In MariaDB, CURRENT_ROLE() is a built-in function that returns the current role name. The current role determines your access privileges.
The output of SELECT CURRENT_ROLE is equivalent to the contents of the information_schema.ENABLED_ROLES table.
MariaDB provides several ways to perform arithmetic on dates. This includes adding or subtracting a year (or many years) from a given date.
Here’s an example of subtracting a year from a date in MariaDB.
Continue readingIn MariaDB, ROW_COUNT() is a built-in function that returns the number of rows updated, inserted or deleted by the preceding statement.
The value returned by ROW_COUNT() is the same as the row count that the mysql client displays and the value from the mysql_affected_rows() C API function.
In MariaDB, LAST_INSERT_ID() is a built-in function that returns the first automatically generated value successfully inserted for an AUTO_INCREMENT column as a result of the most recently executed INSERT statement.
It can also be called with an argument, in which case, it returns the value of the expression and the next call to LAST_INSERT_ID() will return the same value.
In MariaDB, JSON_TABLE() is a built-in function that converts JSON data into a relational form.
In other words, it lets you return a JSON document as a table.
The JSON_TABLE() function was introduced in MariaDB 10.6.0.
MariaDB has an LTRIM() function and a LTRIM_ORACLE() function. Both functions do essentially the same thing. But there is a minor difference.
In MariaDB, DEFAULT() is a built-in function that returns the default value for a table column.
If the column has no default value and it is nullable, then NULL is returned. If the column has no default value and it is not nullable, an error is returned.
Below are 4 functions that enable you to return the seconds part from a time value in MariaDB.
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