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13 <h1 id="pg_hint_plan">pg_hint_plan 1.1 Appendices</h1>
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20 <h2 id="hint-list">Appendix A. Hints list</h2>
21 <p>The available hints are listed below.</p>
25 <tr><th>Group</th><th>Format</th><th>Description</th></tr>
29 <tr><td rowspan="10" nowrap>Scan method</td>
30 <td nowrap>SeqScan(table)</td>
31 <td>Forces sequential scan on the table</td></tr>
32 <tr><td>TidScan(table)</td>
33 <td>Forces TID scan on the table.</td></tr>
34 <tr><td nowrap>IndexScan(table[ index...])</td>
35 <td>Forces index scan on the table. Restricts to specified indexes if any. </td></tr>
36 <tr><td nowrap>IndexOnlyScan(table[ index...])</td>
37 <td>Forces index only scan on the table. Restricts to specfied indexes if any. Index scan may be used if index only scan is not available.</td></tr>
38 <tr><td nowrap>BitmapScan(table[ index...])</td>
39 <td>Forces bitmap scan on the table. Restoricts to specfied indexes if any.</td></tr>
40 <tr><td nowrap>NoSeqScan(table)</td>
41 <td>Forces not to do sequential scan on the table.</td></tr>
42 <tr><td nowrap>NoTidScan(table)</td>
43 <td>Forces not to do TID scan on the table. </td></tr>
44 <tr><td nowrap>NoIndexScan(table)</td>
45 <td>Forces not to do index scan and index only scan on the table. </td></tr>
46 <tr><td nowrap>NoIndexOnlyScan(table)</td>
47 <td>Forces not to do index only scan on the table.</td></tr>
48 <tr><td nowrap>NoBitmapScan(table)</td>
49 <td>Forces not to do bitmap scan on the table. </td></tr>
51 <tr><td rowspan="6" nowrap>Join method</td>
52 <td nowrap>NestLoop(table table[ table...])</td>
53 <td>Forces nested loop for the joins consist of the specifiled tables.</td></tr>
54 <tr><td nowrap>HashJoin(table table[ table...])</td>
55 <td>Forces hash join for the joins consist of the specifiled tables.</td></tr>
56 <tr><td nowrap>MergeJoin(table table[ table...])</td>
57 <td>Forces merge join for the joins consist of the specifiled tables.</td></tr>
58 <tr><td nowrap>NoNestLoop(table table[ table...])</td>
59 <td>Forces not to do nested loop for the joins consist of the specifiled tables.</td></tr>
60 <tr><td nowrap>NoHashJoin(table table[ table...])</td>
61 <td>Forces not to do hash join for the joins consist of the specifiled tables.</td></tr>
62 <tr><td nowrap>NoMergeJoin(table table[ table...])</td>
63 <td>Forces not to do merge join for the joins consist of the specifiled tables.</td></tr>
65 <tr><td rowspan="2">Join order</td>
66 <td nowrap>Leading(table table[ table...])</td>
67 <td>Forces join order as specified.</td></tr>
68 <tr><td nowrap>Leading(<join pair>)</td>
69 <td>Forces join order and directions as specified. A join pair is a pair of tables and/or other join pairs enclosed by parentheses, which can make a nested structure.</td>
71 <tr><td>Row number correction</td>
72 <td nowrap>Rows(table table[ table...] correction)</td>
73 <td>Corrects row number of a result of the joins consist of the specfied tables. The available correction methods are absolute (#<n>), addition (+<n>), subtract (-<n>) and multiplication (*<n>). <n> should be a string that strtod() can read.
75 <td nowrap>Set(GUC-param value)</td>
76 <td>Set the GUC parameter to the value while planner is running.</td></tr>
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