inner join with pivot condition sql - mysql

Question

I currently have the following sql query:
SELECT
name,
SUM( IF( MONTH(date) = 1, amount, 0) ) AS jan,
SUM( IF( MONTH(date) = 2, amount, 0) ) AS feb,
SUM( IF( MONTH(date) = 3, amount, 0) ) AS mar,
SUM( IF( MONTH(date) = 4, amount, 0) ) AS apr,
SUM( IF( MONTH(date) = 5, amount, 0) ) AS mei,
SUM( IF( MONTH(date) = 6, amount, 0) ) AS jun,
SUM( IF( MONTH(date) = 7, amount, 0) ) AS jul,
SUM( IF( MONTH(date) = 8, amount, 0) ) AS agu,
SUM( IF( MONTH(date) = 9, amount, 0) ) AS sep,
SUM( IF( MONTH(date) = 10, amount, 0) ) AS okt,
SUM( IF( MONTH(date) = 11, amount, 0) ) AS nov,
SUM( IF( MONTH(date) = 12, amount, 0) ) AS des,
SUM( amount ) AS total
FROM iuran_detail
WHERE (
date BETWEEN '$date_first' AND '$date_last'
) GROUP BY name;
I want modification with 2 tables sql, user table (along with group) and amount.
I want to combine the inner join or another way, to get the following result (e.g by group A):
thanks

Answer 1

Note: If joining tables it is best practice to prefix EVERY column reference with either the source table name OR by an alias given to the source table (I use the latter). "date" is a terrible column name as it is also used by SQL itself and can cause confusion, so below I have used the MySQL backticks to reference that column, in SQL-Server you could use [date] instead.
SELECT
u.name,
SUM( IF( MONTH(`date`) = 1, d.amount, 0) ) AS jan,
SUM( IF( MONTH(`date`) = 2, d.amount, 0) ) AS feb,
SUM( IF( MONTH(`date`) = 3, d.amount, 0) ) AS mar,
SUM( IF( MONTH(`date`) = 4, d.amount, 0) ) AS apr,
SUM( IF( MONTH(`date`) = 5, d.amount, 0) ) AS mei,
SUM( IF( MONTH(`date`) = 6, d.amount, 0) ) AS jun,
SUM( IF( MONTH(`date`) = 7, d.amount, 0) ) AS jul,
SUM( IF( MONTH(`date`) = 8, d.amount, 0) ) AS agu,
SUM( IF( MONTH(`date`) = 9, d.amount, 0) ) AS sep,
SUM( IF( MONTH(`date`) = 10, d.amount, 0) ) AS okt,
SUM( IF( MONTH(`date`) = 11, d.amount, 0) ) AS nov,
SUM( IF( MONTH(`date`) = 12, d.amount, 0) ) AS des,
SUM( d.amount ) AS total
FROM table_trx d
INNER JOIN table_user u on d.user_id = u.id
WHERE (
d.`date` BETWEEN '$`date`_first' AND '$`date`_last'
) GROUP BY u.name;
Personally I do not like using IF() as an alternative to the more standard CASE expression as it is more broadly supported in SQL databases.
SELECT
u.name,
SUM( case when MONTH(`date`) = 1 then d.amount else 0 end ) AS jan,
SUM( case when MONTH(`date`) = 2 then d.amount else 0 end ) AS feb,
SUM( case when MONTH(`date`) = 3 then d.amount else 0 end ) AS mar,
SUM( case when MONTH(`date`) = 4 then d.amount else 0 end ) AS apr,
SUM( case when MONTH(`date`) = 5 then d.amount else 0 end ) AS mei,
SUM( case when MONTH(`date`) = 6 then d.amount else 0 end ) AS jun,
SUM( case when MONTH(`date`) = 7 then d.amount else 0 end ) AS jul,
SUM( case when MONTH(`date`) = 8 then d.amount else 0 end ) AS agu,
SUM( case when MONTH(`date`) = 9 then d.amount else 0 end ) AS sep,
SUM( case when MONTH(`date`) = 10 then d.amount else 0 end ) AS okt,
SUM( case when MONTH(`date`) = 11 then d.amount else 0 end ) AS nov,
SUM( case when MONTH(`date`) = 12 then d.amount else 0 end ) AS des,
SUM( d.amount ) AS total
FROM table_trx d
INNER JOIN table_user u on d.user_id = u.id
WHERE (
d.`date` BETWEEN '$`date`_first' AND '$`date`_last'
) GROUP BY u.name;