Correlated Sub-Queries:Skip Duplicate

QUERY:

update orders set backlog = "Y"

where exists (

select "X” from items

where orders.order_num = items.order_num

and stock_num = 6 and manu_code = "SMT” )

1) informix.items: INDEX PATH (Skip Duplicate)

Filters: (items.stock_num=6 AND items.manu_code='SMT' )

(1) Index Keys: order_num

2) informix.orders: INDEX PATH

(1) Index Keys: order_num

Lower Index Filter:

orders.order_num = items.order_num

NESTED LOOP JOIN

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