SQL query for calculating aggregated value for only numeric type columns using asterisk

Question

Suppose i have a table which has heterogenous columns(varchar, int, etc).

+-------+----+----+----+
| Nme   | Py | cm | Mt |
+-------+----+----+----+
| johny | 68 | 70 | 66 |
| Harry | 86 | 76 | 90 |
| johny | 18 | 72 | 66 |
+-------+----+----+----+

and in need to calulate sum of each integer column but using some generic sql query such that even if i am adding new integer columns, i won't have to change the query.

What i need but in a generic form

SELECT SUM(Py), SUM(cm), SUM(Mt) FROM table GROUP BY NME;

To something like:

SELECT SUM(*) FROM table WHERE <COLUMNTYPE(INT)> GROUP BY NME;

Is there a way around or it is not possible in SQL?

Answer 1

No such thing. You seem to misunderstand how to use SQL. I think you need a table that "unpivots" your data. Something like:

create table personValues (
    personValues int auto_increment primary key,
    person varchar(255),
    value_type varchar(255),
    value int
);

So, what is now one row would be three rows. You would then get the results in different rows, but you do get the results:

select value_type, sum(value)
from personValues
group by value_type;

If you then need to pivot this to single row, you have two options:

• A pivot using dynamic SQL.
• Using group_concat() to create a long string.

Answer 2

If you want to try dynamic sql for this?

Here's an example snippet for MySql:

-- Adding a test table
drop table if exists test_dynamic;
create table test_dynamic (ID int auto_increment primary key, Nme varchar(30), Py int, Cm int, Mt int);

-- Some sample data
insert into test_dynamic (Nme, Py, Cm, Mt) values
('johny',68,70,66),
('Harry',86,76,90),
('johny',18,72,66);

-- Build a string for the aggregations
set @Sums := (select group_concat(concat(' SUM(', column_name, ') as ', column_name)) as sums
from information_schema.columns
where table_schema = database() 
and table_name = 'test_dynamic'
and data_type = 'int'
and column_key != 'PRI');

-- Stick it to a string for the select
set @DynSql := concat('select 
 Nme, 
', @Sums, '
from test_dynamic
group by Nme
order by Nme');

-- Run the created dynamic sql string
PREPARE stmt FROM @DynSql;
EXECUTE stmt;
DEALLOCATE PREPARE stmt;

Returns:

Nme     Py  Cm  Mt
----    --  --  --
Harry   86  76  90
johny   86  142 132

Answer 3

This code block working in sql server

No single sql statement can do this task.

BEGIN
    DECLARE @ColumnSUM nvarchar(max) = 'NME'

    SELECT @ColumnSUM += ', SUM(' + COLUMN_NAME + ') ' + COLUMN_NAME
      FROM INFORMATION_SCHEMA.COLUMNS
     WHERE TABLE_NAME = 'test_dynamic'
       AND DATA_TYPE = 'int'
       AND COLUMN_NAME != 'ID'

    EXEC('SELECT ' + @ColumnSUM + ' FROM test_dynamic GROUP BY NME ORDER BY NME')
END 

Result:

NME     Py  Cm  Mt
---     --  --  --
Harry   86  76  90
johny   86  142 132