Stream Operation Hints¶
Function¶
These hints specify a stream operation, which can be broadcast or redistribute.
Syntax¶
[no] broadcast|redistribute(table_list)
Parameter Description¶
no indicates that the specified hint will not be used for a join.
table_list specifies the tables to be joined. For details, see Parameter Description.
Examples¶
Hint the query plan in Examples as follows:
explain
select /*+ no redistribute(store_sales store_returns item store) leading(((store_sales store_returns item store) customer)) */ i_product_name product_name ...
In the original plan, the join result of store_sales, store_returns, item, and store is redistributed before it is joined with customer. After the hinting, the redistribution is disabled and the join order is retained. The optimized plan is as follows: