MySQL Common functions

First, CONCAT and Group_concat

1. The CONCAT () function is used to concatenate multiple strings into a single string.

Examples of Use:
SELECT CONCAT (ID, ', ', name) as con from Info LIMIT 1; return result is
+----------+
|con

|
+----------+
| 1,BIOCYC |
+----------+

2. Group_concat often used with GROUP by

The Group_concat function returns a string result that is combined by a value in the grouping

SEPARATOR delimiter

SELECT
Tbl_user.sex,
Group_concat (tbl_user.user_name SEPARATOR ' | | ') As user_name
From
Tbl_user
GROUP by
Tbl_user.sex

Sex user_name
Ladies International Hotel to see | | Normalize the Law of the Republic | | A good sad years and the country | | Send
Men's Republic | | Retro style Wide Sense | | Citi No Fun | | Kerala | | Go home several | | It's very high and high. | Hu Geng | | Share Repurchase | | Personal Unit

Second, date_format

The Date_format () function is used to display date/time data in different formats.

Date_format (Date,format)
The date parameter is a valid day. format Specifies the date/time in which the output is formatted.

Select Date_format (Time, '%y-%m-%d%h:00 ') Datespan,max (bandwith) MaxBandWidth from
TableName where time>= ' 2016-01-01 00:00:00 ' and time< ' 2016-02-24 00:00:00 ' GROUP by Datespan

The output of the Datespan column is timeformat for the date_format specified by the

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MySQL Common functions