| --- |
| title: Using Query Index Hints |
| --- |
| |
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| |
| You can use the hint keyword to allow <%=vars.product_name%>'s query engine to prefer certain indexes. |
| |
| In cases where one index is hinted in a query, the query engine filters off the hinted index (if possible) and then iterates and filters from the resulting values. |
| |
| **Example:** |
| |
| ``` pre |
| <HINT 'IDIndex'> SELECT * FROM /Portfolios p WHERE p.ID > 10 AND p.owner = 'XYZ' |
| ``` |
| |
| If multiple indexes are added as hints, then the query engine will try to use as many indexes as possible while giving a preference for the hinted indexes. |
| |
| **Example:** |
| |
| ``` pre |
| <HINT 'IDIndex', 'OwnerIndex'> SELECT * FROM /Portfolios p WHERE p.ID > 10 AND p.owner = 'XYZ' AND p.value < 100 |
| ``` |
| |
| |