在同一列中获得不同值的单独计数

Question

I want to have separate count for 3 possible values, ie onnet , offnet and international in the same column ( type ) for each distinct user. My table is like this:

number      type
03212889438 onnet
03215350700 international
03212889438 offnet
03455919448 international
03215350700 onnet
03212889438 offnet
03455919448 offnet

So the sums would be:

number      onnet   offnet  international
03212889438 1       2       0
03215350700 1       0       1
03455919448 0       1       1

Then I want to display next to each number its type with the highest count:

number      highest
03212889438 Offnet
03215350700 Onnet
03455010448 Offnet

Answer 1

To get first result you will be required to use pivot table concept as below

    SELECT
    number,
    COUNT(CASE WHEN type = 'onnet' THEN id ELSE NULL END) AS onnet,
    COUNT(CASE WHEN type = 'offnet' THEN id ELSE NULL END) AS offnet,
    COUNT(CASE WHEN type = 'international' THEN id ELSE NULL END) AS international
FROM
    test2
GROUP BY
    number;

SELECT   number,
         CASE GREATEST(
           count(type='onnet'),
           count(type='offnet'),
           count(type='international')
         )
           WHEN count(type='onnet')         THEN 'onnet'
           WHEN count(type='offnet')        THEN 'offnet'
           WHEN count(type='international') THEN 'international'
         END AS highest
FROM     test2
GROUP BY number;

above query will give you output as required

see sql fiddle

Answer 2

You need to group your records using a suitable aggregate function; in MySQL one can do:

SELECT   number,
         SUM(type='onnet')         AS onnet,
         SUM(type='offnet')        AS offnet,
         SUM(type='international') AS international
FROM     my_table
GROUP BY number;

SELECT   number,
         CASE GREATEST(
           SUM(type='onnet'),
           SUM(type='offnet'),
           SUM(type='international')
         )
           WHEN SUM(type='onnet')         THEN 'onnet'
           WHEN SUM(type='offnet')        THEN 'offnet'
           WHEN SUM(type='international') THEN 'international'
         END AS highest
FROM     my_table
GROUP BY number;

See it on sqlfiddle .