Concepts of banner and general tables

Now the conversion method is listed as follows:

1, the longitudinal table to the horizontal table:

TableA structure of the longitudinal table

Name	Course	Grade
Tom	Chinese	75
Tom	Mathematical	80
Tom	English	90
John doe	Chinese	95
John doe	Mathematical	55

Horizontal table Structure TableB

Name	Chinese	Mathematical	English
Tom	75	80	90
John doe	95	55	0

Method One:

Select Name,

SUM (case Course "language" then Grade else 0 end) as language,

SUM (case Course when ' math ' then Grade else 0 end) as mathematics,

SUM (case Course when ' English ' then Grade else 0 end) as English

From TableA

GROUP BY Name

2. "SQL" example of horizontal table to table
Horizontal table structure: test_h2z
ID name Chinese Math english
1 Sheets 380 90 70
2 Lee 490 85 95
3 Wang 588 75 90

The converted table structure:
ID Name Account Score
1 in three languages 80
2 Zhang Three Mathematics 90
3 three English 70
4 John Doe Language 90
5 John Doe Mathematics 80
6 John Doe English 99
7 Harry Language 85
8 Harry Mathematics 96
9 Harry English 88
Table of horizontal Tables SQL example:
SELECT name, ' language ' as subject, language as score from test_h2z UNION all
SELECT name, ' Math ' as subject, math as score from test_h2z UNION all
SELECT name, ' English ' as subject, English as score from test_h2z
ORDER by name, subject DESC;

Concepts of banner and general tables