Querying and SQL Functions

Single row functions work on one

Single row functions work on one row at a time and return one result for each row. They are also called scalar functions and can be used in the SELECT

POWER(X

POWER(X,Y) or POW(X,Y) calculates X to the power Y. ROUND(N,D) rounds a number to D decimal places, and MOD(A,B) returns the remainder after dividing

String functions work on character data

String functions work on character data. UCASE or UPPER changes text to uppercase, LOWER or LCASE changes text to lowercase, MID or SUBSTRING or SUBST

NOW() returns the current system date

NOW() returns the current system date and time. DATE(), MONTH(), MONTHNAME(), YEAR(), DAY(), and DAYNAME() extract parts of a date or time value.

Aggregate functions are also called multiple

Aggregate functions are also called multiple row functions. They work on a set of rows and return a single value. MAX, MIN, AVG, SUM, COUNT, and COUNT