sql - MySQL Join three tables return multiple results -


i have 3 tables: let's call customer, log , review

the customer table is:

id name == ==== 1  john 2  jane 3  mike

the log table is

id customer_id  created_at == ===========  ========== 1  1            2015-06-10 2  1            2015-06-10 3  2            2015-06-11 4  1            2015-06-13 5  2            2015-06-15 6  1            2015-06-15

the review table is

id customer_id  created_at == ===========  ========== 1  1            2015-06-10 2  2            2015-06-10 3  2            2015-06-11 4  1            2015-06-13 5  1            2015-06-15 6  1            2015-06-15 7  1            2015-06-18

what wanted

customer_id name log_qty review_qty =========== ==== ======= ========== 1           john 4       5 2           jane 2       2 3           mike 0       0

what got:

customer_id name log_qty review_qty =========== ==== ======= ========== 1           john 20      20 2           jane 4       4 3           mike 0       0

my query:

                       select customer.id, customer.name,  count(review.customer_id) review_qty,     count(log.customer_id) log_qty                          customer                     left join review                            on review.customer_id = customer.id                     left join log                            on log.customer_id = customer.id                      group customer.id                      order customer.id

if run query without count() , group by, you'll see what's happening:

select customer.id, customer.name,  review.customer_id review_qty,  log.customer_id log_qty customer  left join review on review.customer_id = customer.id  left join log on log.customer_id = customer.id order customer.id

this returns row each possible combination of rows same customer_id 3 tables (that's inner join does). count counts 'em!

this should give need:

select customer.id, customer.name,  (select count(*) review customer_id = customer.id) review_qty,  (select count(*) log customer_id = customer.id)  log_qty customer order customer.id

-

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