temporary table has a count for each other table - mysql

Question

I'm trying to make a statistics page in my php script. in order to select the count from each table I need more than 30 Queries like this
SELECT COUNT(order_id) as `uncompleted_orders` FROM `orders` WHERE `order_status` != 0
and then I need to run another query like this:
SELECT COUNT(order_id) as `completed_orders` FROM `orders` WHERE `order_status` = 1
I've tried this approach, but it didn't work:
SELECT COUNT(order_id) as `uncompleted_orders` FROM `sd_orders` WHERE `order_status` != 4;
SELECT COUNT(order_id) as `completed_orders` FROM `sd_orders` WHERE `order_status` = 4;
Is there any way to creat a new temp table in MySQL contains the count for other tables?

Answer 1

You could try something like this:
SELECT
(
SELECT COUNT(order_id) FROM `sd_orders` WHERE `order_status` != 4
) as `uncompleted_orders`,
(
SELECT COUNT(order_id) FROM `sd_orders` WHERE `order_status` = 4
) as `completed_orders`
You will have a result set with one row and a field for each count.

Answer 2

Without more information it's impossible to generalise, but there are many constructs that can help you here.
First, your example is actually from one table, and not two. This means that you can do the following...
SELECT
COUNT(CASE WHEN order_status = 4 THEN order_id END) AS complete_orders,
COUNT(CASE WHEN order_status <> 4 THEN order_id END) AS incomplete_orders
FROM
sd_orders
This works because COUNT(<something>) doesn't include an NULLs in the results. And by not including an ELSE clause, anything that doesn't match returns NULL. Another way people accomplish the same result is SUM(CASE WHEN ? THEN 1 ELSE 0 END).
Second, where you do actually have multiple tables, you can combine the results in several different ways...
-- Where you want one value from each table...
--------------------------------------------------------------------------------
SELECT
(SELECT COUNT(*) FROM table1 WHERE fieldx = ?) AS value1,
(SELECT COUNT(*) FROM table2 WHERE fieldy = ?) AS value2
-- Where you want one row of values from each table...
--------------------------------------------------------------------------------
SELECT
table1_summary.value1 AS table1_value1,
table1_summary.value2 AS table1_value2,
table2_summary.value1 AS table2_value1,
table2_summary.value2 AS table2_value2
FROM
(
SELECT
COUNT(CASE WHEN fieldx = ? THEN id END) AS value1,
COUNT(CASE WHEN fieldx <> ? THEN id END) AS value2
FROM
table1
)
AS table1_summary
CROSS JOIN
(
SELECT
COUNT(CASE WHEN fieldy = ? THEN id END) AS value1,
COUNT(CASE WHEN fieldy <> ? THEN id END) AS value2
FROM
table2
)
AS table2_summary
-- Where you want many rows, but of the same fields, from each table...
--------------------------------------------------------------------------------
SELECT
*
FROM
(
SELECT
'Table1' AS source_table,
fielda AS some_grouping,
COUNT(CASE WHEN fieldx = ? THEN id END) AS value1,
COUNT(CASE WHEN fieldx <> ? THEN id END) AS value2
FROM
table1
GROUP BY
fielda
UNION ALL
SELECT
'Table2' AS source_table,
fieldb AS some_grouping,
COUNT(CASE WHEN fieldy = ? THEN id END) AS value1,
COUNT(CASE WHEN fieldy <> ? THEN id END) AS value2
FROM
table2
GROUP BY
fieldb
)
AS summary
ORDER BY
source_table,
some_grouping,
value1,
value2
As you can see, there are a lot of ways to do this. How you approach it totally depends on your data and your needs.