In MariaDB, the COUNT()
aggregate function returns a count of the number of non-NULL values of an expression in the rows retrieved by a SELECT
statement.
Tag: functions
AVG() Function in MariaDB
In MariaDB, the AVG()
function returns the average value of the given expression.
The DISTINCT
option can be used to return the average of the distinct values (i.e. remove duplicates before calculating the average).
NULL
values are ignored.
SUM() Function in MariaDB
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 readingHAS_DBACCESS() – Discover if a User Can Access a Database in SQL Server
SQL Server has a HAS_DBACCESS()
function that returns information about whether the user has access to a specified database.
MIN() Function in MariaDB
In MariaDB, MIN()
is an aggregate function that returns the minimum value in a given expression.
MAX() Function in MariaDB
In MariaDB, MAX()
is an aggregate function that returns the maximum value in a given expression.
2 Ways to List all Functions in MariaDB
Below are two options for returning a list of functions in MariaDB.
Continue readingPostgreSQL GROUP_CONCAT() Equivalent
Some 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.
SQL LPAD()
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).
SQL RPAD()
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.