SQL Aggregation #

Do some calculations.

Other than count(), many of the methods require numeric value types.

COUNT() #

SELECT count(*) --or <field(s)>
FROM <table>;

Extend with conditions

SELECT count(*) --or <field(s)>
FROM <table>
WHERE <condition>;

SUM() #

SELECT sum(<field>)
FROM <table>;

MAX() #

SELECT MAX(<field>)
FROM <table>;

MIN() #

SELECT MIN(<field>)
FROM <table>;

AVG() #

SELECT MIN(<field>)
FROM <table>;

ROUND() #

round(<field>, <integer>), where the integer specifies the number of decimal place s to round to.

GROUP BY #

Aggregate by a particular group

SELECT <field>
FROM <table>
GROUP BY <categorical field>;

GROUP BY can also be performed on a calculation.