Join Methods: Nested Loop Join

QUERY:

select * from stock, items

where stock.stock_num = items.stock_num

and items.quantityɭ

Estimated Cost: 9

Estimated # of Rows Returned: 22

1) informix.stock: SEQUENTIAL SCAN

2) informix.items: INDEX PATH

Filters: informix.items.quantity > 1

(1) Index Keys: stock_num manu_code

Lower Index Filter:items.stock_num = stock.stock_num

Notice the index on the joined column

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