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IMPALA-6912: [DOCS] A new query option COMPUTE_STATS_MIN_SAMPLE_SIZE

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Change-Id: Ibd6f55a4c6c99185baf7974f68935ba4e03579df
Reviewed-on: http://gerrit.cloudera.org:8080/10172
Reviewed-by: Alex Behm <alex.behm@cloudera.com>
Tested-by: Impala Public Jenkins <impala-public-jenkins@cloudera.com>
This commit is contained in:
Alex Rodoni
2018-04-23 22:10:53 -07:00
committed by Impala Public Jenkins
parent 1dcc6c1beb
commit da7f865f05
3 changed files with 49 additions and 0 deletions
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docs/impala.ditamap
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@@ -175,6 +175,7 @@ under the License.
<topicref href="topics/impala_batch_size.xml"/>
<topicref rev="2.10.0 IMPALA-3200" href="topics/impala_buffer_pool_limit.xml"/>
<topicref href="topics/impala_compression_codec.xml"/>
<topicref href="topics/impala_compute_stats_min_sample_size.xml"/>
<topicref href="topics/impala_debug_action.xml"/>
<topicref rev="2.9.0" href="topics/impala_decimal_v2.xml"/>
<topicref rev="2.9.0 IMPALA-5381" href="topics/impala_default_join_distribution_mode.xml"/>

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docs/impala_keydefs.ditamap
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@@ -10776,6 +10776,7 @@ under the License.
<keydef href="topics/impala_batch_size.xml" keys="batch_size"/>
<keydef rev="2.10.0 IMPALA-3200" href="topics/impala_buffer_pool_limit.xml" keys="buffer_pool_limit"/>
<keydef href="topics/impala_compression_codec.xml" keys="compression_codec"/>
<keydef href="topics/impala_compute_stats_min_sample_size.xml" keys="comute_stats_min_sample_size"/>
<keydef href="topics/impala_debug_action.xml" keys="debug_action"/>
<keydef href="topics/impala_default_join_distribution_mode.xml" keys="default_join_distribution_mode"/>
<keydef rev="2.10.0 IMPALA-3200" href="topics/impala_default_spillable_buffer_size.xml" keys="default_spillable_buffer_size"/>

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docs/topics/impala_compute_stats_min_sample_size.xml Normal file
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<?xml version="1.0" encoding="UTF-8"?>
<!--
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specific language governing permissions and limitations
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-->
<!DOCTYPE concept PUBLIC "-//OASIS//DTD DITA Concept//EN" "concept.dtd">
<concept id="compute_stats_sample_min_sample_size" rev="2.12.0">
<title>COMPUTE_STATS_MIN_SAMPLE_SIZE Query Option</title>
<titlealts audience="PDF">
<navtitle>COMPUTE_STATS_MIN_SAMPLE_SIZE</navtitle>
</titlealts>
<prolog>
<metadata>
<data name="Category" value="Impala"/>
<data name="Category" value="Impala Query Options"/>
<data name="Category" value="Querying"/>
<data name="Category" value="Developers"/>
<data name="Category" value="Data Analysts"/>
</metadata>
</prolog>
<conbody>
<p>The <codeph>COMPUTE_STATS_MIN_SAMPLE_SIZE</codeph> query option specifies
the minimum number of bytes that will be scanned in <codeph>COMPUTE STATS
TABLESAMPLE</codeph>, regardless of the user-supplied sampling percent.
This query option prevents sampling for very small tables where accurate
stats can be obtained cheaply without sampling because the minimum sample
size is required to get meaningful stats.</p>
<p conref="../shared/impala_common.xml#common/type_integer"/>
<p><b>Default:</b> 1GB</p>
<p><b>Added in</b>: <keyword keyref="impala212_full"/></p>
<p conref="../shared/impala_common.xml#common/usage_notes_blurb"/>
</conbody>
</concept>