EDIT: Updated with Bill Carvin's suggestions below. Still very slow.
I am trying to write a query that will find all the items in an order that is entered into a warehouse that does not have an entry for this item in this warehouse. For example, if an XYZ item is entered for storage A, but stock A does not actually have an XYZ item, I want the order item to appear in my report.
I can run the query just fine, but it seems to take forever (50 seconds). It seems that it hangs mainly in the "zero" state, which I have in the where clause. If I delete the condition with "null" and run it, it will execute in approximately 4.8 s. Here is my request:
SELECT
saw_order.Wo,
saw_orderitem.Item,
saw_orderitem.Stock,
saw_order.`Status`,
saw_order.`Date`,
saw_orderitem.Warehouse,
saw_stockbalance.Balno,
saw_stockbalance.Stock
FROM
saw_order
Inner Join saw_orderitem ON saw_order.Wo = saw_orderitem.Wo
Inner Join saw_stock ON saw_orderitem.Stock = saw_stock.Stock
Left Join saw_stockbalance ON saw_orderitem.Stock = saw_stockbalance.Stock
AND saw_orderitem.Warehouse = saw_stockbalance.Warehouse
WHERE
saw_order.`Status` Between 3 and 81 and
saw_stockbalance.Stock Is Null
explain , :
+----+-------------+------------------+--------+------------------------------+---------+---------+-------------------------------------------------------+-------+-------------------------+
| id | select_type | table | type | possible_keys | key | key_len | ref | rows | Extra |
+----+-------------+------------------+--------+------------------------------+---------+---------+-------------------------------------------------------+-------+-------------------------+
| 1 | SIMPLE | saw_stock | index | PRIMARY | PRIMARY | 17 | NULL | 32793 | Using index |
| 1 | SIMPLE | saw_orderitem | ref | PRIMARY,Stock,StockWarehouse | Stock | 17 | saws.saw_stock.Stock | 68 | |
| 1 | SIMPLE | saw_order | eq_ref | PRIMARY,Status | PRIMARY | 4 | saws.saw_orderitem.Wo | 1 | Using where |
| 1 | SIMPLE | saw_stockbalance | ref | Stock,Warehouse | Stock | 20 | saws.saw_orderitem.Stock,saws.saw_orderitem.Warehouse | 1 | Using where; Not exists |
+----+-------------+------------------+--------+------------------------------+---------+---------+-------------------------------------------------------+-------+-------------------------+
, , , , .
EDIT: , :
mysql> show index from saw_order;
+-----------+------------+----------+--------------+-------------+-----------+-------------+----------+--------+------+------------+---------+
| Table | Non_unique | Key_name | Seq_in_index | Column_name | Collation | Cardinality | Sub_part | Packed | Null | Index_type | Comment |
+-----------+------------+----------+--------------+-------------+-----------+-------------+----------+--------+------+------------+---------+
| saw_order | 0 | PRIMARY | 1 | Wo | A | 553425 | NULL | NULL | | BTREE | |
| saw_order | 1 | Customer | 1 | Customer | A | 14957 | NULL | NULL | | BTREE | |
| saw_order | 1 | Other | 1 | Other | A | 218 | NULL | NULL | | BTREE | |
| saw_order | 1 | Site | 1 | Site | A | 8 | NULL | NULL | | BTREE | |
| saw_order | 1 | Date | 1 | Date | A | 1594 | NULL | NULL | | BTREE | |
| saw_order | 1 | Status | 1 | Status | A | 15 | NULL | NULL | | BTREE | |
+-----------+------------+----------+--------------+-------------+-----------+-------------+----------+--------+------+------------+---------+
6 rows in set
mysql> show index from saw_orderitem;
+---------------+------------+----------------+--------------+-------------+-----------+-------------+----------+--------+------+------------+---------+
| Table | Non_unique | Key_name | Seq_in_index | Column_name | Collation | Cardinality | Sub_part | Packed | Null | Index_type | Comment |
+---------------+------------+----------------+--------------+-------------+-----------+-------------+----------+--------+------+------------+---------+
| saw_orderitem | 0 | PRIMARY | 1 | Wo | A | NULL | NULL | NULL | | BTREE | |
| saw_orderitem | 0 | PRIMARY | 2 | Item | A | 1842359 | NULL | NULL | | BTREE | |
| saw_orderitem | 1 | Stock | 1 | Stock | A | 27093 | NULL | NULL | | BTREE | |
| saw_orderitem | 1 | Product | 1 | Product | A | 803 | NULL | NULL | | BTREE | |
| saw_orderitem | 1 | GGroup | 1 | GGroup | A | 114 | NULL | NULL | | BTREE | |
| saw_orderitem | 1 | ShipVia | 1 | ShipVia | A | 218 | NULL | NULL | | BTREE | |
| saw_orderitem | 1 | Warehouse | 1 | Warehouse | A | 9 | NULL | NULL | | BTREE | |
| saw_orderitem | 1 | StockWarehouse | 1 | Stock | A | 27093 | NULL | NULL | | BTREE | |
| saw_orderitem | 1 | StockWarehouse | 2 | Warehouse | A | 49793 | NULL | NULL | | BTREE | |
+---------------+------------+----------------+--------------+-------------+-----------+-------------+----------+--------+------+------------+---------+
9 rows in set
mysql> show index from saw_stock;
+-----------+------------+-------------------+--------------+-------------------+-----------+-------------+----------+--------+------+------------+---------+
| Table | Non_unique | Key_name | Seq_in_index | Column_name | Collation | Cardinality | Sub_part | Packed | Null | Index_type | Comment |
+-----------+------------+-------------------+--------------+-------------------+-----------+-------------+----------+--------+------+------------+---------+
| saw_stock | 0 | PRIMARY | 1 | Stock | A | 32793 | NULL | NULL | | BTREE | |
| saw_stock | 1 | Class | 1 | Class | A | 655 | NULL | NULL | YES | BTREE | |
| saw_stock | 1 | DateFirstReceived | 1 | DateFirstReceived | A | 2732 | NULL | NULL | | BTREE | |
+-----------+------------+-------------------+--------------+-------------------+-----------+-------------+----------+--------+------+------------+---------+
3 rows in set
mysql> show index from saw_stockbalance;
+------------------+------------+-----------+--------------+-------------+-----------+-------------+----------+--------+------+------------+---------+
| Table | Non_unique | Key_name | Seq_in_index | Column_name | Collation | Cardinality | Sub_part | Packed | Null | Index_type | Comment |
+------------------+------------+-----------+--------------+-------------+-----------+-------------+----------+--------+------+------------+---------+
| saw_stockbalance | 0 | PRIMARY | 1 | Balno | A | 146315 | NULL | NULL | | BTREE | |
| saw_stockbalance | 1 | Stock | 1 | Stock | A | 36578 | NULL | NULL | | BTREE | |
| saw_stockbalance | 1 | Stock | 2 | Warehouse | A | 146315 | NULL | NULL | | BTREE | |
| saw_stockbalance | 1 | Warehouse | 1 | Warehouse | A | 11 | NULL | NULL | | BTREE | |
+------------------+------------+-----------+--------------+-------------+-----------+-------------+----------+--------+------+------------+---------+
4 rows in set
?