Here is the list of all important MySQL functions. Each function has been explained along with suitable example. * MySQL Group By Clause - The MySQL GROUP BY statement is used along with the SQL aggregate functions like SUM to provide means of grouping the result dataset by certain database table column(s). * MySQL IN Clause - This is a clause which can be used alongwith any MySQL query to specify a condition. * MySQL BETWEEN Clause - This is a clause which can be used alongwith any MySQL query to specify a condition. * MySQL UNION Keyword - Use a UNION operation to combine multiple result sets into one. * MySQL COUNT Function - The MySQL COUNT aggregate function is used to count the number of rows in a database table. * MySQL MAX Function - The MySQL MAX aggregate function allows us to select the highest (maximum) value for a certain column. * MySQL MIN Function - The MySQL MIN aggregate function allows us to select the lowest (minimum) value for a certain column. * MySQL AVG Function - The MySQL AVG aggregate function selects the average value for certain table column. * MySQL SUM Function - The MySQL SUM aggregate function allows selecting the total for a numeric column. * MySQL SQRT Functions - This is used to generate a square root of a given number. * MySQL RAND Function - This is used to generate a random number using MySQL command. * MySQL CONCAT Function - This is used to concatenate any string inside any MySQL command. * MySQL DATE and Time Functions - Complete list of MySQL Date and Time related functions. * MySQL Numeric Functions - Complete list of MySQL functions required to manipulate numbers in MySQL. * MySQL String Functions - Complete list of MySQL functions required to manipulate strings in MySQL.