What's wrong with my SQL? (MySQL syntax error, code 1064) - mysql

Question

I have
select created_at, sales_flat_order.customer_id,
customer_firstname, customer_lastname, customer_email,
sales_flat_order_address.company,
SUM(grand_total)
from sales_flat_order
left join sales_flat_order_address
on sales_flat_order.entity_id = sales_flat_order_address.entity_id
where created_at >= '2016-06-01 05:00:00' /* 5h difference */
and store_id = 1
and `status` = 'Complete'/*
left join customer_entity
on sales_flat_order.customer_id = customer_entity.entity_id*/
group by customer_email;
Runs fine. Comment content produces error with SQL syntax, code 1064. What's the problem?
Same issue now with this:
select customer.entity_id, customer.group_id,
customer.created_at,
sfo.customer_firstname, sfo.customer_lastname,
sfo.customer_email,
sfo.created_at last_order,
count(sfo.customer_id) num_orders,
group_concat(sfo.grand_total separator '|') grand_totals
from customer_entity customer
inner join sales_flat_order sfo
on customer.entity_id = sfo.customer_id
where sfo.created_at >= '2016-06-01 05:00:00'
and sfo.store_id = 1
and sfo.`status` = 'Complete'
left outer join customer_group
on customer.group_id = customer.customer_group_id
where customer_group.customer_group_id
group by customer.entity_id;
Thanks everyone, that all makes ample sense, definitely getting into the hang of it; how's this? It works but tear it up if anything remains amuck.
select customer.entity_id, customer.group_id, `group`.customer_group_code,
customer.created_at,
`order`.customer_firstname, `order`.customer_lastname,
`order`.customer_email, address.company,
`order`.created_at last_order,
count(`order`.customer_id) num_orders,
group_concat(`order`.grand_total separator '|') grand_totals
from customer_entity customer
inner join sales_flat_order `order`
on customer.entity_id = `order`.customer_id
left outer join customer_group `group`
on customer.group_id = `group`.customer_group_id
left outer join sales_flat_order_address address
on `order`.entity_id = address.entity_id
where `order`.created_at >= '2016-06-01 05:00:00'
and `order`.store_id = 1
and `order`.`status` = 'Complete'
group by customer.entity_id;
I know everyone said to add to the group by clause but there is nothing else I want to group by...?

Answer 1

The where clause must be after all of the joins. There are other issues as well, but that's the issue that really breaks things.
If it were me, I'd also fix the group by clause to match the select list, but MySql lets you write non-standard SQL in this way. You may also have a naming conflict when you add the additional table because you haven't qualified the column names. Aliases would make this easier to do Finally, it's possible for your query logic that you want some of the conditional expressions in the where clause to be part of the first ON clause.

Answer 2

If you format your code properly, it's easy to see why your code doesn't work. Your commented LEFT JOIN that caused the error is after the WHERE clause. Also write proper SQL. Alias your table name because long column names are annoying. Put all non-aggregated columns in the GROUP BY clause. Your code won't even run in any other dbms except for maybe MySQL.
select created_at, sales_flat_order.customer_id
, customer_firstname, customer_lastname
, customer_email
, sales_flat_order_address.company
, SUM(grand_total)
from sales_flat_order
left join sales_flat_order_address on sales_flat_order.entity_id = sales_flat_order_address.entity_id
where created_at >= '2016-06-01 05:00:00' /* 5h difference */
and store_id = 1
and `status` = 'Complete'/*
left join customer_entity on sales_flat_order.customer_id = customer_entity.entity_id*/
group by customer_email;