创建MySQL的列和行

Question

I have table data such as this

index  user  date   rank
  11     a    1Mar    23
  12     b    1Mar    16
  13     a    2Mar    24
  14     b    2Mar    18

What I would like to achieve via a query is this:

    1Mar   2Mar
a   23     24
b   16     18 

I don't know if this can be done via a single statement at the command line or if this will have to be done via a form and some scripting. Doing through scripting I can do, but can't see how to do in a single statement.

Answer 1

you can do pivot like below, if you know all possible values for date or you need to use dynamic sql.

SELECT user,
       MAX( CASE WHEN date ='1Mar' THEN rank else NULL end) AS '1Mar',
       MAX( CASE WHEN date ='2Mar' THEN rank else NULL end) AS '2Mar'
FROM Table1
GROUP BY user