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MySQL statistics sum Select Sum

黄舟

Dec 27, 2016 pm 05:35 PM

mysqlselect

Sum of statistical data

SELECT SUM() FROM syntax is used to calculate the sum of statistical data from the data table.

Syntax:

SELECT SUM(column) FROM tb_name

This SQL syntax is used to count the sum of values of a certain numerical type field. SUM() cannot contain multiple fields. Although string and other types can be executed, Meaningless.

Example:

SELECT SUM(uid) FROM user

Get query results:

Statistical maximum data

SELECT MAX() FROM syntax is used to extract data from the data table Count the maximum data of a certain field.

Syntax:

SELECT MAX(column) FROM tb_name

This SQL syntax is used to count the maximum value of a certain numerical type field. There cannot be multiple fields in MAX().

Example:

SELECT MAX(uid) FROM user

Get the query results:

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