What is the function used to query results in mysql?

Functions used in MySQL for query results include: Aggregation functions: Calculate the sum, average, minimum, maximum, or number of rows. String functions: concatenate, extract, replace or get the length of a string. Mathematical functions: take absolute value, round, round up or down. Date and time functions: get date and time, extract date or time part. Other functions: get the first non-NULL value, compare expressions for equality, get the maximum or minimum value, etc.

Functions used to query results in MySQL

MySQL provides a series of functions for retrieval and Manipulate data in the database. These functions are mainly divided into the following categories:

Aggregation function

• SUM(): Calculate the sum of the values ​​of the specified column
• AVG (): Calculate the average value of the specified column
• MIN(): Get the minimum value of the specified column
• MAX(): Get the maximum value of the specified column
• COUNT (): Count the number of rows that meet the specified conditions

String function

• CONCAT(): Concatenate two or more strings
• SUBSTRING(): Extract part of the string
• REPLACE(): Replace part of the string
• LENGTH(): Get the length of the string

Mathematical functions

##ABS(): Take the absolute value
• ROUND(): Round the number
• CEILING() : Round up
• FLOOR(): Round down

Date and time functions

NOW(): Get the current date and time
• DATE(): Get only the date part
• TIME(): Get only the time part
• YEAR(): Get the year
• MONTH(): Get the month
• DAY(): Get the date

Other functions

COALESCE(): Get The first non-NULL value
• NULLIF(): If the two expressions are equal, return NULL
• GREATEST(): Get the largest value
• LEAST(): Get the minimum value

These functions can be used individually or in combination to obtain the desired query results. They enable developers to efficiently retrieve and process data from MySQL databases.

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