Learn how to use SQL's basic aggregation functions like COUNT, SUM, AVG, MAX, and MIN in this step-by-step tutorial!

Advanced SQL Aggregation Tutorial: [ Ссылка ]

Queries:
1) Get a count of all the rows: SELECT COUNT(*) FROM table
2) Get a SUM of a column in all the rows: SELECT SUM(column1) FROM table
3) Get the maxium number in a column: SELECT MAX(column1) FROM table
4) Get the minimum number in a column: SELECT MIN(column1) FROM table
5) You can also do arithmatic with these aggregate functions: SELECT MAX(column1)-MIN(column1) AS range FROM table
6) Or, like this: SELECT AVG(column1*column2) FROM table

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