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| <li>Summary: </li> |
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| <div class="sub-title"><span class="package-label-in-type">Package</span> <a href="package-summary.html">org.apache.calcite.rel.hint</a></div> |
| <h1 title="Class RelHint" class="title">Class RelHint</h1> |
| </div> |
| <div class="inheritance" title="Inheritance Tree"><a href="https://docs.oracle.com/javase/9/docs/api/java/lang/Object.html" title="class or interface in java.lang" class="external-link">java.lang.Object</a> |
| <div class="inheritance">org.apache.calcite.rel.hint.RelHint</div> |
| </div> |
| <section class="class-description" id="class-description"> |
| <hr> |
| <div class="type-signature"><span class="modifiers">public class </span><span class="element-name type-name-label">RelHint</span> |
| <span class="extends-implements">extends <a href="https://docs.oracle.com/javase/9/docs/api/java/lang/Object.html" title="class or interface in java.lang" class="external-link">Object</a></span></div> |
| <div class="block">Hint attached to a relation expression. |
| |
| <p>A hint can be used to: |
| |
| <ul> |
| <li>Enforce planner: there's no perfect planner, so it makes sense to implement hints to |
| allow user better control the execution. For instance, "never merge this subquery with others", |
| "treat those tables as leading ones" in the join ordering, etc.</li> |
| <li>Append meta data/statistics: Some statistics like “table index for scan” and |
| “skew info of some shuffle keys” are somewhat dynamic for the query, it would be very |
| convenient to config them with hints because our planning metadata from the planner is very |
| often not that accurate.</li> |
| <li>Operator resource constraints: For many cases, we would give a default resource |
| configuration for the execution operators, i.e. min parallelism or |
| managed memory (resource consuming UDF) or special resource requirement (GPU or SSD disk) |
| and so on, it would be very flexible to profile the resource with hints per query |
| (instead of the Job).</li> |
| </ul> |
| |
| <p>In order to support hint override, each hint has a <code>inheritPath</code> (integers list) to |
| record its propagate path from the root node, number `0` represents the hint was propagated |
| along the first(left) child, number `1` represents the hint was propagated along the |
| second(right) child. Given a relational expression tree with initial attached hints: |
| |
| <blockquote><pre> |
| Filter (Hint1) |
| | |
| Join |
| / \ |
| Scan Project (Hint2) |
| | |
| Scan2 |
| </pre></blockquote> |
| |
| <p>The plan would have hints path as follows (assumes each hint can be propagated to all |
| child nodes): |
| |
| <blockquote><ul> |
| <li>Filter → {Hint1[]}</li> |
| <li>Join → {Hint1[0]}</li> |
| <li>Scan → {Hint1[0, 0]}</li> |
| <li>Project → {Hint1[0,1], Hint2[]}</li> |
| <li>Scan2 → {[Hint1[0, 1, 0], Hint2[0]}</li> |
| </ul></blockquote> |
| |
| <p><code>listOptions</code> and <code>kvOptions</code> are supposed to contain the same information, |
| they are mutually exclusive, that means, they can not both be non-empty. |
| |
| <p>RelHint is immutable.</div> |
| </section> |
| <section class="summary"> |
| <ul class="summary-list"> |
| <!-- ======== NESTED CLASS SUMMARY ======== --> |
| <li> |
| <section class="nested-class-summary" id="nested-class-summary"> |
| <h2>Nested Class Summary</h2> |
| <div class="caption"><span>Nested Classes</span></div> |
| <div class="summary-table three-column-summary"> |
| <div class="table-header col-first">Modifier and Type</div> |
| <div class="table-header col-second">Class</div> |
| <div class="table-header col-last">Description</div> |
| <div class="col-first even-row-color"><code>static class </code></div> |
| <div class="col-second even-row-color"><code><a href="RelHint.Builder.html" class="type-name-link" title="class in org.apache.calcite.rel.hint">RelHint.Builder</a></code></div> |
| <div class="col-last even-row-color"> |
| <div class="block">Builder for <a href="RelHint.html" title="class in org.apache.calcite.rel.hint"><code>RelHint</code></a>.</div> |
| </div> |
| </div> |
| </section> |
| </li> |
| <!-- =========== FIELD SUMMARY =========== --> |
| <li> |
| <section class="field-summary" id="field-summary"> |
| <h2>Field Summary</h2> |
| <div class="caption"><span>Fields</span></div> |
| <div class="summary-table three-column-summary"> |
| <div class="table-header col-first">Modifier and Type</div> |
| <div class="table-header col-second">Field</div> |
| <div class="table-header col-last">Description</div> |
| <div class="col-first even-row-color"><code>final <a href="https://docs.oracle.com/javase/9/docs/api/java/lang/String.html" title="class or interface in java.lang" class="external-link">String</a></code></div> |
| <div class="col-second even-row-color"><code><a href="#hintName" class="member-name-link">hintName</a></code></div> |
| <div class="col-last even-row-color"> </div> |
| <div class="col-first odd-row-color"><code>final com.google.common.collect.ImmutableList<<a href="https://docs.oracle.com/javase/9/docs/api/java/lang/Integer.html" title="class or interface in java.lang" class="external-link">Integer</a>></code></div> |
| <div class="col-second odd-row-color"><code><a href="#inheritPath" class="member-name-link">inheritPath</a></code></div> |
| <div class="col-last odd-row-color"> </div> |
| <div class="col-first even-row-color"><code>final <a href="https://docs.oracle.com/javase/9/docs/api/java/util/Map.html" title="class or interface in java.util" class="external-link">Map</a><<a href="https://docs.oracle.com/javase/9/docs/api/java/lang/String.html" title="class or interface in java.lang" class="external-link">String</a>,<wbr><a href="https://docs.oracle.com/javase/9/docs/api/java/lang/String.html" title="class or interface in java.lang" class="external-link">String</a>></code></div> |
| <div class="col-second even-row-color"><code><a href="#kvOptions" class="member-name-link">kvOptions</a></code></div> |
| <div class="col-last even-row-color"> </div> |
| <div class="col-first odd-row-color"><code>final <a href="https://docs.oracle.com/javase/9/docs/api/java/util/List.html" title="class or interface in java.util" class="external-link">List</a><<a href="https://docs.oracle.com/javase/9/docs/api/java/lang/String.html" title="class or interface in java.lang" class="external-link">String</a>></code></div> |
| <div class="col-second odd-row-color"><code><a href="#listOptions" class="member-name-link">listOptions</a></code></div> |
| <div class="col-last odd-row-color"> </div> |
| </div> |
| </section> |
| </li> |
| <!-- ========== METHOD SUMMARY =========== --> |
| <li> |
| <section class="method-summary" id="method-summary"> |
| <h2>Method Summary</h2> |
| <div id="method-summary-table"> |
| <div class="table-tabs" role="tablist" aria-orientation="horizontal"><button id="method-summary-table-tab0" role="tab" aria-selected="true" aria-controls="method-summary-table.tabpanel" tabindex="0" onkeydown="switchTab(event)" onclick="show('method-summary-table', 'method-summary-table', 3)" class="active-table-tab">All Methods</button><button id="method-summary-table-tab1" role="tab" aria-selected="false" aria-controls="method-summary-table.tabpanel" tabindex="-1" onkeydown="switchTab(event)" onclick="show('method-summary-table', 'method-summary-table-tab1', 3)" class="table-tab">Static Methods</button><button id="method-summary-table-tab2" role="tab" aria-selected="false" aria-controls="method-summary-table.tabpanel" tabindex="-1" onkeydown="switchTab(event)" onclick="show('method-summary-table', 'method-summary-table-tab2', 3)" class="table-tab">Instance Methods</button><button id="method-summary-table-tab4" role="tab" aria-selected="false" aria-controls="method-summary-table.tabpanel" tabindex="-1" onkeydown="switchTab(event)" onclick="show('method-summary-table', 'method-summary-table-tab4', 3)" class="table-tab">Concrete Methods</button></div> |
| <div id="method-summary-table.tabpanel" role="tabpanel"> |
| <div class="summary-table three-column-summary" aria-labelledby="method-summary-table-tab0"> |
| <div class="table-header col-first">Modifier and Type</div> |
| <div class="table-header col-second">Method</div> |
| <div class="table-header col-last">Description</div> |
| <div class="col-first even-row-color method-summary-table method-summary-table-tab1 method-summary-table-tab4"><code>static <a href="RelHint.Builder.html" title="class in org.apache.calcite.rel.hint">RelHint.Builder</a></code></div> |
| <div class="col-second even-row-color method-summary-table method-summary-table-tab1 method-summary-table-tab4"><code><a href="#builder(java.lang.String)" class="member-name-link">builder</a><wbr>(<a href="https://docs.oracle.com/javase/9/docs/api/java/lang/String.html" title="class or interface in java.lang" class="external-link">String</a> hintName)</code></div> |
| <div class="col-last even-row-color method-summary-table method-summary-table-tab1 method-summary-table-tab4"> |
| <div class="block">Creates a hint builder with specified hint name.</div> |
| </div> |
| <div class="col-first odd-row-color method-summary-table method-summary-table-tab2 method-summary-table-tab4"><code><a href="RelHint.html" title="class in org.apache.calcite.rel.hint">RelHint</a></code></div> |
| <div class="col-second odd-row-color method-summary-table method-summary-table-tab2 method-summary-table-tab4"><code><a href="#copy(java.util.List)" class="member-name-link">copy</a><wbr>(<a href="https://docs.oracle.com/javase/9/docs/api/java/util/List.html" title="class or interface in java.util" class="external-link">List</a><<a href="https://docs.oracle.com/javase/9/docs/api/java/lang/Integer.html" title="class or interface in java.lang" class="external-link">Integer</a>> inheritPath)</code></div> |
| <div class="col-last odd-row-color method-summary-table method-summary-table-tab2 method-summary-table-tab4"> |
| <div class="block">Returns a copy of this hint with specified inherit path.</div> |
| </div> |
| <div class="col-first even-row-color method-summary-table method-summary-table-tab2 method-summary-table-tab4"><code>boolean</code></div> |
| <div class="col-second even-row-color method-summary-table method-summary-table-tab2 method-summary-table-tab4"><code><a href="#equals(java.lang.Object)" class="member-name-link">equals</a><wbr>(@Nullable <a href="https://docs.oracle.com/javase/9/docs/api/java/lang/Object.html" title="class or interface in java.lang" class="external-link">Object</a> o)</code></div> |
| <div class="col-last even-row-color method-summary-table method-summary-table-tab2 method-summary-table-tab4"> </div> |
| <div class="col-first odd-row-color method-summary-table method-summary-table-tab2 method-summary-table-tab4"><code>int</code></div> |
| <div class="col-second odd-row-color method-summary-table method-summary-table-tab2 method-summary-table-tab4"><code><a href="#hashCode()" class="member-name-link">hashCode</a>()</code></div> |
| <div class="col-last odd-row-color method-summary-table method-summary-table-tab2 method-summary-table-tab4"> </div> |
| <div class="col-first even-row-color method-summary-table method-summary-table-tab2 method-summary-table-tab4"><code><a href="https://docs.oracle.com/javase/9/docs/api/java/lang/String.html" title="class or interface in java.lang" class="external-link">String</a></code></div> |
| <div class="col-second even-row-color method-summary-table method-summary-table-tab2 method-summary-table-tab4"><code><a href="#toString()" class="member-name-link">toString</a>()</code></div> |
| <div class="col-last even-row-color method-summary-table method-summary-table-tab2 method-summary-table-tab4"> </div> |
| </div> |
| </div> |
| </div> |
| <div class="inherited-list"> |
| <h3 id="methods-inherited-from-class-java.lang.Object">Methods inherited from class java.lang.<a href="https://docs.oracle.com/javase/9/docs/api/java/lang/Object.html" title="class or interface in java.lang" class="external-link">Object</a></h3> |
| <code><a href="https://docs.oracle.com/javase/9/docs/api/java/lang/Object.html#clone()" title="class or interface in java.lang" class="external-link">clone</a>, <a href="https://docs.oracle.com/javase/9/docs/api/java/lang/Object.html#finalize()" title="class or interface in java.lang" class="external-link">finalize</a>, <a href="https://docs.oracle.com/javase/9/docs/api/java/lang/Object.html#getClass()" title="class or interface in java.lang" class="external-link">getClass</a>, <a href="https://docs.oracle.com/javase/9/docs/api/java/lang/Object.html#notify()" title="class or interface in java.lang" class="external-link">notify</a>, <a href="https://docs.oracle.com/javase/9/docs/api/java/lang/Object.html#notifyAll()" title="class or interface in java.lang" class="external-link">notifyAll</a>, <a href="https://docs.oracle.com/javase/9/docs/api/java/lang/Object.html#wait()" title="class or interface in java.lang" class="external-link">wait</a>, <a href="https://docs.oracle.com/javase/9/docs/api/java/lang/Object.html#wait(long)" title="class or interface in java.lang" class="external-link">wait</a>, <a href="https://docs.oracle.com/javase/9/docs/api/java/lang/Object.html#wait(long,int)" title="class or interface in java.lang" class="external-link">wait</a></code></div> |
| </section> |
| </li> |
| </ul> |
| </section> |
| <section class="details"> |
| <ul class="details-list"> |
| <!-- ============ FIELD DETAIL =========== --> |
| <li> |
| <section class="field-details" id="field-detail"> |
| <h2>Field Details</h2> |
| <ul class="member-list"> |
| <li> |
| <section class="detail" id="inheritPath"> |
| <h3>inheritPath</h3> |
| <div class="member-signature"><span class="modifiers">public final</span> <span class="return-type">com.google.common.collect.ImmutableList<<a href="https://docs.oracle.com/javase/9/docs/api/java/lang/Integer.html" title="class or interface in java.lang" class="external-link">Integer</a>></span> <span class="element-name">inheritPath</span></div> |
| </section> |
| </li> |
| <li> |
| <section class="detail" id="hintName"> |
| <h3>hintName</h3> |
| <div class="member-signature"><span class="modifiers">public final</span> <span class="return-type"><a href="https://docs.oracle.com/javase/9/docs/api/java/lang/String.html" title="class or interface in java.lang" class="external-link">String</a></span> <span class="element-name">hintName</span></div> |
| </section> |
| </li> |
| <li> |
| <section class="detail" id="listOptions"> |
| <h3>listOptions</h3> |
| <div class="member-signature"><span class="modifiers">public final</span> <span class="return-type"><a href="https://docs.oracle.com/javase/9/docs/api/java/util/List.html" title="class or interface in java.util" class="external-link">List</a><<a href="https://docs.oracle.com/javase/9/docs/api/java/lang/String.html" title="class or interface in java.lang" class="external-link">String</a>></span> <span class="element-name">listOptions</span></div> |
| </section> |
| </li> |
| <li> |
| <section class="detail" id="kvOptions"> |
| <h3>kvOptions</h3> |
| <div class="member-signature"><span class="modifiers">public final</span> <span class="return-type"><a href="https://docs.oracle.com/javase/9/docs/api/java/util/Map.html" title="class or interface in java.util" class="external-link">Map</a><<a href="https://docs.oracle.com/javase/9/docs/api/java/lang/String.html" title="class or interface in java.lang" class="external-link">String</a>,<wbr><a href="https://docs.oracle.com/javase/9/docs/api/java/lang/String.html" title="class or interface in java.lang" class="external-link">String</a>></span> <span class="element-name">kvOptions</span></div> |
| </section> |
| </li> |
| </ul> |
| </section> |
| </li> |
| <!-- ============ METHOD DETAIL ========== --> |
| <li> |
| <section class="method-details" id="method-detail"> |
| <h2>Method Details</h2> |
| <ul class="member-list"> |
| <li> |
| <section class="detail" id="builder(java.lang.String)"> |
| <h3>builder</h3> |
| <div class="member-signature"><span class="modifiers">public static</span> <span class="return-type"><a href="RelHint.Builder.html" title="class in org.apache.calcite.rel.hint">RelHint.Builder</a></span> <span class="element-name">builder</span><wbr><span class="parameters">(<a href="https://docs.oracle.com/javase/9/docs/api/java/lang/String.html" title="class or interface in java.lang" class="external-link">String</a> hintName)</span></div> |
| <div class="block">Creates a hint builder with specified hint name.</div> |
| </section> |
| </li> |
| <li> |
| <section class="detail" id="copy(java.util.List)"> |
| <h3>copy</h3> |
| <div class="member-signature"><span class="modifiers">public</span> <span class="return-type"><a href="RelHint.html" title="class in org.apache.calcite.rel.hint">RelHint</a></span> <span class="element-name">copy</span><wbr><span class="parameters">(<a href="https://docs.oracle.com/javase/9/docs/api/java/util/List.html" title="class or interface in java.util" class="external-link">List</a><<a href="https://docs.oracle.com/javase/9/docs/api/java/lang/Integer.html" title="class or interface in java.lang" class="external-link">Integer</a>> inheritPath)</span></div> |
| <div class="block">Returns a copy of this hint with specified inherit path.</div> |
| <dl class="notes"> |
| <dt>Parameters:</dt> |
| <dd><code>inheritPath</code> - Hint path</dd> |
| <dt>Returns:</dt> |
| <dd>the new <code>RelHint</code></dd> |
| </dl> |
| </section> |
| </li> |
| <li> |
| <section class="detail" id="equals(java.lang.Object)"> |
| <h3>equals</h3> |
| <div class="member-signature"><span class="modifiers">public</span> <span class="return-type">boolean</span> <span class="element-name">equals</span><wbr><span class="parameters">(@Nullable <a href="https://docs.oracle.com/javase/9/docs/api/java/lang/Object.html" title="class or interface in java.lang" class="external-link">Object</a> o)</span></div> |
| <dl class="notes"> |
| <dt>Overrides:</dt> |
| <dd><code><a href="https://docs.oracle.com/javase/9/docs/api/java/lang/Object.html#equals(java.lang.Object)" title="class or interface in java.lang" class="external-link">equals</a></code> in class <code><a href="https://docs.oracle.com/javase/9/docs/api/java/lang/Object.html" title="class or interface in java.lang" class="external-link">Object</a></code></dd> |
| </dl> |
| </section> |
| </li> |
| <li> |
| <section class="detail" id="hashCode()"> |
| <h3>hashCode</h3> |
| <div class="member-signature"><span class="modifiers">public</span> <span class="return-type">int</span> <span class="element-name">hashCode</span>()</div> |
| <dl class="notes"> |
| <dt>Overrides:</dt> |
| <dd><code><a href="https://docs.oracle.com/javase/9/docs/api/java/lang/Object.html#hashCode()" title="class or interface in java.lang" class="external-link">hashCode</a></code> in class <code><a href="https://docs.oracle.com/javase/9/docs/api/java/lang/Object.html" title="class or interface in java.lang" class="external-link">Object</a></code></dd> |
| </dl> |
| </section> |
| </li> |
| <li> |
| <section class="detail" id="toString()"> |
| <h3>toString</h3> |
| <div class="member-signature"><span class="modifiers">public</span> <span class="return-type"><a href="https://docs.oracle.com/javase/9/docs/api/java/lang/String.html" title="class or interface in java.lang" class="external-link">String</a></span> <span class="element-name">toString</span>()</div> |
| <dl class="notes"> |
| <dt>Overrides:</dt> |
| <dd><code><a href="https://docs.oracle.com/javase/9/docs/api/java/lang/Object.html#toString()" title="class or interface in java.lang" class="external-link">toString</a></code> in class <code><a href="https://docs.oracle.com/javase/9/docs/api/java/lang/Object.html" title="class or interface in java.lang" class="external-link">Object</a></code></dd> |
| </dl> |
| </section> |
| </li> |
| </ul> |
| </section> |
| </li> |
| </ul> |
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