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| <meta name="DC.Title" content="BROADCAST_BYTES_LIMIT Query Option" /> |
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| <h1 class="title topictitle1" id="ariaid-title1">BROADCAST_BYTES_LIMIT Query Option</h1> |
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| <div class="body conbody"> |
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| <p class="p"> |
| Sets the limit |
| for the size of the broadcast input based on estimated size. |
| </p> |
| |
| <p class="p"> |
| The Impala planner may in rare cases make a bad choice to broadcast a large table or intermediate |
| result and encounter performance problems due to high memory pressure. Setting this limit will |
| make the planner pick a partition based hash join instead of broadcast and avoid such performance problems. |
| </p> |
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| <p class="p"> |
| <strong class="ph b">Type:</strong> integer |
| </p> |
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| <p class="p"> |
| <strong class="ph b">Default:</strong> |
| </p> |
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| <p class="p"> |
| The default value is 34359738368 (32 GB). A value of 0 causes the option to be ignored. |
| </p> |
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| <p class="p"> |
| <strong class="ph b">Examples:</strong> |
| </p> |
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| <pre class="pre codeblock"><code> |
| -- Change the limit to 16GB. |
| set broadcast_bytes_limit=17179869184; |
| |
| -- Disable the BROADCAST_BYTES_LIMIT. |
| set broadcast_bytes_limit=0; |
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| </code></pre> |
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| <div class="related-links"> |
| <div class="familylinks"> |
| <div class="parentlink"><strong>Parent topic:</strong> <a class="link" href="../topics/impala_set.html">SET Statement</a></div> |
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