In MariaDB, the SUM()
aggregate function returns the sum of a given expression.
It can also be used to return the sum of all distinct (unique) values in an expression.
Continue readingIn MariaDB, the SUM()
aggregate function returns the sum of a given expression.
It can also be used to return the sum of all distinct (unique) values in an expression.
Continue readingSQL Server has a HAS_DBACCESS()
function that returns information about whether the user has access to a specified database.
In MariaDB, MIN()
is an aggregate function that returns the minimum value in a given expression.
In MariaDB, MAX()
is an aggregate function that returns the maximum value in a given expression.
Below are two options for returning a list of functions in MariaDB.
Continue readingSome RDBMSs like MySQL and MariaDB have a GROUP_CONCAT()
function that allows you to return a query column as a delimited list (for example, a comma separated list).
PostgreSQL has a similar function called STRING_AGG()
. This function works in pretty much the same way that GROUP_CONCAT()
works in MySQL and MariaDB.
In SQL, LPAD()
is a commonly used function that pads the left part of a string with a specified character. The function can be used on strings and numbers, although depending on the DBMS, numbers may have to be passed as a string before they can be padded.
DBMSs that have an LPAD()
function include MySQL, MariaDB, PostgreSQL, and Oracle.
DBMSs that don’t have an LPAD()
function include SQL Server and SQLite (although there are other ways to apply left padding in these DBMSs).
In SQL, RPAD()
is used to pad the right part of a string with a specified character. The function can be used on strings and numbers, although depending on the DBMS, numbers may have to be passed as a string before they can be padded.
DBMSs that have an RPAD()
function include MySQL, MariaDB, PostgreSQL, and Oracle.
DBMSs that don’t have an RPAD()
function include SQL Server and SQLite.
Some RDBMSs have a GROUP_CONCAT()
function that allows you to return a query column as a delimited list (for example, a comma separated list). MySQL and MariaDB are two that have such a function.
PostgreSQL and SQL Server have similar functions called STRING_AGG()
.
Oracle, on the other hand, has the LISTAGG()
function that does pretty much the same thing (and perhaps more).
So you could say that LISTAGG()
is Oracle’s GROUP_CONCAT()
equivalent.
In MySQL, the JSON_VALUE()
function extracts a value from a JSON document at the specified path.
The function was introduced in MySQL 8.0.21.
Continue reading