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IMPALA-9029: [DOCS] Impala 3.4 Release Notes
-Added broadcast_bytes_limit query option
Change-Id: I4385749de35f8379ecf6566fe515ed500b42d6cc
Reviewed-on: http://gerrit.cloudera.org:8080/14863
Tested-by: Impala Public Jenkins <impala-public-jenkins@cloudera.com>
Reviewed-by: Joe McDonnell <joemcdonnell@cloudera.com>
(cherry picked from commit 955868f88a)
This commit is contained in:
Alex Rodoni
committed by
Joe McDonnell
Joe McDonnell
parent
3a0515a1a6
commit
f0e09a55ab
@@ -1519,8 +1519,7 @@ alter table partitioned_data set tblproperties ('numRows'='1030000', 'STATS_GENE
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or <codeph>-f</codeph> options are used.
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</p>
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<p id="live_progress_live_summary_asciinema">
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To see how the <codeph>LIVE_PROGRESS</codeph> and <codeph>LIVE_SUMMARY</codeph> query
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<p id="live_progress_live_summary_asciinema">To see how the <codeph>LIVE_PROGRESS</codeph> and <codeph>LIVE_SUMMARY</codeph> query
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options work in real time, see
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<xref href="https://asciinema.org/a/1rv7qippo0fe7h5k1b6k4nexk" scope="external" format="html">this
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animated demo</xref>.
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@@ -50,6 +50,26 @@ under the License.
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</p>
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<p outputclass="toc inpage"/>
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</conbody>
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<concept id="incompatible_changes_340x">
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<title>Incompatible Changes Introduced in Impala 3.4.x</title>
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<conbody>
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<p> For the full list of issues closed in this release, including any that
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introduce behavior changes or incompatibilities, see the <xref
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keyref="changelog_34">changelog for <keyword keyref="impala34"
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/></xref>. <ul>
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<li>To optimize query performance, Impala planner uses the value of
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the <codeph>fs.s3a.block.size</codeph> startup flag when calculating
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the split size on non-block based stores, e.g. S3, ADLS, etc.
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Starting in this release, Impala planner uses the
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<codeph>PARQUET_OBJECT_STORE_SPLIT_SIZE</codeph> query option to
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get the Parquet file format specific split size.<p>For Parquet
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files, the <codeph>fs.s3a.block.size</codeph> startup flag is no
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longer used.</p><p>The default value of the
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<codeph>PARQUET_OBJECT_STORE_SPLIT_SIZE</codeph> query option is
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256 MB.</p></li>
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</ul></p>
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</conbody>
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</concept>
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<concept id="incompatible_changes_330x">
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<title>Incompatible Changes Introduced in Impala 3.3.x</title>
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<conbody>
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@@ -259,162 +259,6 @@ under the License.
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</concept>
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<!--IMPALA-7585 and IMPALA-7298 are fixed. Should be removed from here?-->
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<concept id="IMPALA-7585" audience="hidden">
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<title>Impala user not added to /etc/passwd when LDAP is enabled</title>
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<conbody>
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<p>
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When using Impala with LDAP enabled, a user may hit the following:
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</p>
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<pre>Not authorized: Client connection negotiation failed: client connection to 127.0.0.1:27000: SASL(-1): generic failure: All-whitespace username.</pre>
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<p>
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The following sequence can lead to the <codeph>impala</codeph> user not being created
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in <codeph>/etc/passwd</codeph> on some machines on the cluster.
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<ul>
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<li>
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Time 1: The <codeph>impala</codeph> user is not in LDAP. Impala was installed on
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machine 1, and the user <codeph>impala</codeph> is created in
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<codeph>/etc/passwd</codeph>.
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</li>
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<li>
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Time 2: The <codeph>impala</codeph> user is added to LDAP.
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</li>
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<li>
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Time 3: A new machine is added to the cluster. When adding Impala service to this
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new machine, adding the <codeph>impala</codeph> user will fail as it already
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exists in LDAP.
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</li>
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</ul>
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</p>
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<p>
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The consequence is that the <codeph>impala</codeph> user doesn't exist in
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<codeph>/etc/passwd</codeph> on the new machine, leading to the error above.
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</p>
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<p>
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<b>Workaround</b>: Manually edit <codeph>/etc/passwd</codeph> to add the
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<codeph>impala</codeph> user
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</p>
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<p>
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<b>Apache Issue:</b> <xref keyref="IMPALA-7585">IMPALA-7585</xref>
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</p>
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<p>
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<b>Affected Versions:</b> Impala 2.12, Impala 3.0
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</p>
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<p>
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<b>Fixed Version:</b> Impala 3.1
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</p>
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</conbody>
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</concept>
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<concept id="IMPALA-7298" audience="hidden">
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<title>Kerberos authentication fails with the reverse DNS lookup disabled</title>
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<conbody>
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|
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<p>
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Kerberos authentication does not function correctly if <codeph>rdns = false</codeph>
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is configured in <codeph>krb5.conf</codeph>. If the flag <codeph>rdns =
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false</codeph>, when Impala tries to match principals, it will fail because Kerberos
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receives a SPN (Service Principal Name) with an IP address in it, but Impala expects a
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principal with a FQDN in it.
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</p>
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<p>
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You may hit the following error:
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</p>
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<pre>WARNINGS: TransmitData() to X.X.X.X:27000 failed: Not authorized: Client connection negotiation failed: client connection to X.X.X.X:27000: Server impala/X.X.X.X@VPC.CLOUDERA.COM not found in Kerberos database
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</pre>
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<p>
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<b>Apache Issue:</b> <xref keyref="IMPALA-7298">IMPALA-7298</xref>
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</p>
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<p>
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<b>Affected Versions:</b> Impala 2.12.0 and 3.0
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</p>
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<p>
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<b>Workaround:</b> Set the following flags in <codeph>krb5.conf</codeph>:
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<ul>
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<li>
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<codeph>dns_canonicalize_hostname = true</codeph>
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</li>
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<li>
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<codeph>rdns = true</codeph>
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</li>
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</ul>
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</p>
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<p>
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<b>Fixed Versions:</b> Impala 3.1
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</p>
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</conbody>
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</concept>
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<!--kudu2198 is fixed-->
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<concept id="KUDU-2198" audience="hidden">
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<title>System-wide auth-to-local mapping not applied correctly to Kudu service account</title>
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<conbody>
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<p>
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Due to system the <codeph>auth_to_local</codeph> mapping, the principal may be mapped
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to some local name.
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</p>
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<p>
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When running with Kerberos enabled, you may hit the following error message where
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<varname><random-string></varname> is some random string which doesn't match the
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primary in the Kerberos principal.
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</p>
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<pre>WARNINGS: TransmitData() to X.X.X.X:27000 failed: Remote error: Not authorized: {username='<random-string>', principal='impala/redacted'} is not allowed to access DataStreamService
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</pre>
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<p>
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<b>Workaround</b>: Start Impala with the
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<codeph>--use_system_auth_to_local=false</codeph> flag to ignore the system-wide
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<codeph>auth_to_local</codeph> mappings configured in <codeph>/etc/krb5.conf</codeph>.
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</p>
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<p>
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<b>Apache Issue:</b> <xref keyref="IMPALA-8154">IMPALA-8154</xref>
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</p>
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<p>
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<b>Affected Versions:</b> Impala 2.12, Impala 3.0 / Kudu 1.6
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</p>
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<p>
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<b>Fixed Versions:</b> Impala 3.2
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</p>
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</conbody>
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||||
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||||
</concept>
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</concept>
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<concept id="known_issues_resources">
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@@ -722,25 +566,6 @@ ALTER TABLE table_name SET TBLPROPERTIES('EXTERNAL'='TRUE');
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</concept>
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<concept id="IMP-175" audience="hidden">
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<title>Deviation from Hive behavior: Out of range values float/double values are returned as maximum allowed value of type (Hive returns NULL)</title>
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<conbody>
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<p>
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Impala behavior differs from Hive with respect to out of range float/double values.
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Out of range values are returned as maximum allowed value of type (Hive returns NULL).
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</p>
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<p>
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<b>Workaround:</b> None
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</p>
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|
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</conbody>
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|
||||
</concept>
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|
||||
<concept id="flume_writeformat_text">
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||||
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||||
<title>Configuration needed for Flume to be compatible with Impala</title>
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@@ -837,6 +662,24 @@ ALTER TABLE table_name SET TBLPROPERTIES('EXTERNAL'='TRUE');
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</conbody>
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||||
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||||
</concept>
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<concept id="IMPALA-8953">
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||||
<title>Tables and databases sharing same name can cause query
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failures</title>
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<conbody>
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<p>A table and a database that share the same name can cause a query
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failure if the table is not readable by Impala, for example, the table
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was created in Hive in the Open CSV Serde format. The following
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exception will return:</p>
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<codeblock>CAUSED BY: TableLoadingException: Unrecognized table type for table</codeblock>
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<p>
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<b>Apache Issue:</b>
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<xref keyref="IMPALA-8953">IMPALA-8953</xref>
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</p>
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<p>
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<b>Workaround:</b> Do not create databases and tables with the same
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names.</p>
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</conbody>
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||||
</concept>
|
||||
|
||||
</concept>
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||||
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@@ -852,22 +695,6 @@ ALTER TABLE table_name SET TBLPROPERTIES('EXTERNAL'='TRUE');
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</p>
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||||
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||||
</conbody>
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||||
<!--IMPALA8376 fixed the issue below.-->
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<concept id="IMPALA-8829" audience="hidden">
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<title>Unable to Correctly Parse the Terabyte Unit</title>
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<conbody>
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<p>Impala does not support parsing strings that contain "TB" when used
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as a unit for terabytes. The flags related to memory limits may be
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affected, such as the flags for scratch space and data cache.</p>
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<p><b>Workaround:</b> Use other supported units to specify values, e.g.
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GB or MB.</p>
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<p><b>Affected Versions:</b> All versions</p>
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||||
<p>
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||||
<b>Apache Issue:</b>
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||||
<xref keyref="IMPALA-8829">IMPALA-8829</xref>
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</p>
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||||
</conbody>
|
||||
</concept>
|
||||
|
||||
<concept id="IMPALA-4551">
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||||
|
||||
@@ -989,33 +816,6 @@ ALTER TABLE table_name SET TBLPROPERTIES('EXTERNAL'='TRUE');
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||||
</concept>
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||||
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<!--Fixed in 3.2-->
|
||||
|
||||
<concept id="IMPALA-941" rev="IMPALA-941" audience="hidden">
|
||||
|
||||
<title>Impala Parser issue when using fully qualified table names that start with a number</title>
|
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|
||||
<conbody>
|
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|
||||
<p>
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A fully qualified table name starting with a number could cause a parsing error. In a
|
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name such as <codeph>db.571_market</codeph>, the decimal point followed by digits is
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interpreted as a floating-point number.
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</p>
|
||||
|
||||
<p>
|
||||
<b>Apache Issue:</b> <xref keyref="IMPALA-941">IMPALA-941</xref>
|
||||
</p>
|
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|
||||
<p>
|
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<b>Workaround:</b> Surround each part of the fully qualified name with backticks
|
||||
(<codeph>``</codeph>).
|
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</p>
|
||||
|
||||
</conbody>
|
||||
|
||||
</concept>
|
||||
|
||||
<concept id="IMPALA-532" rev="IMPALA-532">
|
||||
|
||||
<title>Impala should tolerate bad locale settings</title>
|
||||
|
||||
@@ -45,6 +45,185 @@ under the License.
|
||||
<p outputclass="toc inpage"/>
|
||||
|
||||
</conbody>
|
||||
<concept rev="3.2.0" id="new_features_34">
|
||||
<title>New Features in <keyword keyref="impala34"/></title>
|
||||
<conbody>
|
||||
<p> The following sections describe the noteworthy improvements made in
|
||||
<keyword keyref="impala34"/>. </p>
|
||||
<p> For the full list of issues closed in this release, see the <xref
|
||||
keyref="changelog_34">changelog for <keyword keyref="impala34"
|
||||
/></xref>. </p>
|
||||
<section id="section_cw4_nmw_pjb">
|
||||
<title>Support for Hive Insert-Only Transactional Tables</title>
|
||||
<p>Impala added the support to truncate insert-only transactional
|
||||
tables. </p>
|
||||
<p>By default, Impala creates an insert-only transactional table when
|
||||
you issue the <codeph>CREATE TABLE</codeph> statement.</p>
|
||||
<p>Use the Hive compaction to compact small files to improve the
|
||||
performance and scalability of metadata in transactional tables.</p>
|
||||
<p>See <xref href="impala_transactions.xml#transactions"/> for more
|
||||
information.</p>
|
||||
</section>
|
||||
<section id="impala-8656">
|
||||
<title>Server-side Spooling of Query Results</title>
|
||||
<p>You can use the <codeph>SPOOL_QUERY_RESULTS</codeph> query option to
|
||||
control how query results are returned to the client.</p>
|
||||
<p>By default, when a client fetches a set of query results, the next
|
||||
set of results are fetched in batches until all the result rows are
|
||||
produced. If a client issues a query without fetching all the results,
|
||||
the query fragments continue to hold on to the resources until the
|
||||
query is canceled and unregistered, potentially tying up resources and
|
||||
causing other queries to wait in admission control.</p>
|
||||
<p>When the query result spooling feature is enabled, the result sets of
|
||||
queries are eagerly fetched and buffered until they are read by the
|
||||
client, and resources are freed up for other queries.</p>
|
||||
<p>See <xref href="impala_query_results_spooling.xml#data_sink"/> for
|
||||
the new feature and the query options.</p>
|
||||
</section>
|
||||
<section id="impala-8584">
|
||||
<title>Cookie-based Authentication</title>
|
||||
<p>Starting in this version, Impala supports cookies for authentication
|
||||
when clients connect via HiveServer2 over HTTP. </p>
|
||||
<p>You can use the <codeph>--max_cookie_lifetime_s startup</codeph> flag
|
||||
to:</p>
|
||||
<ul>
|
||||
<li>Disable the use of cookies</li>
|
||||
<li>Control how long generated cookies are valid for</li>
|
||||
</ul>
|
||||
<p>See <xref href="impala_client.xml#intro_client"/> for more
|
||||
information.</p>
|
||||
</section>
|
||||
<section id="section_hw4_nmw_pjb">
|
||||
<title>Object Ownership Support</title>
|
||||
<p>Object ownership for tables, views, and databases is enabled by
|
||||
default in Impala. When you create a database, a table, or a view, as
|
||||
the owner of that object, you implicitly have the privileges on the
|
||||
object. The privileges that owners have are specified in Ranger on the
|
||||
special user, <codeph>{OWNER}</codeph>. </p>
|
||||
<p>The <codeph>{OWNER}</codeph> user must be defined in Ranger for the
|
||||
object ownership privileges work in Impala.</p>
|
||||
<p>See <xref href="impala_authorization.xml#authorization"/> for
|
||||
details.</p>
|
||||
</section>
|
||||
<section id="impala-8752">
|
||||
<title>New Built-in Functions for Fuzzy Matching of Strings</title>
|
||||
<p>Use the new Jaro or Jaro-Winkler functions to perform fuzzy matches
|
||||
on relatively short strings, e.g. to scrub user inputs of names
|
||||
against the records in the database.</p>
|
||||
<ul>
|
||||
<li><codeph>JARO_DISTANCE</codeph>, <codeph>JARO_DST</codeph></li>
|
||||
<li><codeph>JARO_SIMILARITY</codeph>, <codeph>JARO_SIM</codeph></li>
|
||||
<li><codeph>JARO_WINKLER_DISTANCE</codeph>,
|
||||
<codeph>JW_DST</codeph></li>
|
||||
<li><codeph>JARO_WINKLER_SIMILARITY</codeph>,
|
||||
<codeph>JW_SIM</codeph></li>
|
||||
</ul>
|
||||
<p>See <xref href="impala_string_functions.xml#string_functions"/> for
|
||||
details.</p>
|
||||
</section>
|
||||
<section id="impala-8376">
|
||||
<title>Capacity Quota for Scratch Disks</title>
|
||||
<p>When configuring scratch space for intermediate files used in large
|
||||
sorts, joins, aggregations, or analytic function operations, use the
|
||||
<codeph>‑‑scratch_dirs</codeph> startup flag to optionally specify a
|
||||
capacity quota per scratch directory, e.g.,
|
||||
<codeph>‑‑scratch_dirs=/dir1:5MB,/dir2</codeph>.</p>
|
||||
<p>See <xref href="impala_file_formats.xml#file_formats"/> for
|
||||
details.</p>
|
||||
</section>
|
||||
<section id="impala-8913">
|
||||
<title>Query Option for Disabling HBase Row Estimation</title>
|
||||
<p>During query plan generation, Impala samples underlying HBase tables
|
||||
to estimate row count and row size, but the sampling process can
|
||||
negatively impact the planning time. To alleviate the issue, when the
|
||||
HBase table stats do not change much in a short time, disable the
|
||||
sampling with the <codeph>DISABLE_HBASE_NUM_ROWS_ESTIMATE</codeph>
|
||||
query option so that the Impala planner falls back to using Hive
|
||||
Metastore (HMS) table stats instead. </p>
|
||||
<p>See <xref
|
||||
href="impala_disable_hbase_num_rows_estimate.xml#disable_hbase_num_rows_estimate"
|
||||
/>.</p>
|
||||
</section>
|
||||
<section id="impala-8942">
|
||||
<title>Query Option for Controlling Size of Parquet Splits on Non-block
|
||||
Stores</title>
|
||||
<p>To optimize query performance, Impala planner uses the value of the
|
||||
<codeph>fs.s3a.block.size</codeph> startup flag when calculating the
|
||||
split size on non-block based stores, e.g. S3, ADLS, etc. Starting in
|
||||
this release, Impala planner uses the
|
||||
<codeph>PARQUET_OBJECT_STORE_SPLIT_SIZE</codeph> query option to get
|
||||
the Parquet file format specific split size. </p>
|
||||
<p>For Parquet files, the <codeph>fs.s3a.block.size</codeph> startup
|
||||
flag is no longer used.</p>
|
||||
<p>The default value of the
|
||||
<codeph>PARQUET_OBJECT_STORE_SPLIT_SIZE</codeph> query option is 256
|
||||
MB.</p>
|
||||
<p>See <xref href="impala_s3.xml#s3"/> for tuning Impala query
|
||||
performance for S3.</p>
|
||||
</section>
|
||||
<section id="impala-5149">
|
||||
<title>Query Profile Exported to JSON</title>
|
||||
<p>On the Query Details page of Impala Daemon Web UI, you have a new
|
||||
option, in addition to the existing Thrift and Text formats, to export
|
||||
the query profile output in the JSON format.</p>
|
||||
<p>See <xref href="impala_webui.xml#webui"/> for generating JSON query
|
||||
profile outputs in Web UI.</p>
|
||||
</section>
|
||||
<section id="section_rnb_ny4_yjb">
|
||||
<title>DATE Data Type Supported in Avro Tables</title>
|
||||
<p>You can now use the <codeph>DATE</codeph> data type to query date
|
||||
values from Avro tables.</p>
|
||||
<p>See <xref href="impala_avro.xml#avro"/> for details.</p>
|
||||
</section>
|
||||
<section>
|
||||
<title>Primary Key and Foreign Key Constraints</title>
|
||||
<p>This release adds support for primary and foreign key constraints,
|
||||
but in this release the constraints are advisory and intended for
|
||||
estimating cardinality during query planning in a future release.
|
||||
There is no attempt to enforce constraints. See <xref
|
||||
href="impala_create_table.xml"/> for details. </p>
|
||||
</section>
|
||||
<section>
|
||||
<title>Enhanced External Kudu Table</title>
|
||||
<p>By default HMS implicitly translates internal Kudu tables to external
|
||||
Kudu tables with the 'external.table.purge' property set to true. These
|
||||
tables behave similar to internal tables. You can explicitly create such
|
||||
external Kudu tables. See <xref href="impala_create_table.xml"/>
|
||||
for details.</p>
|
||||
</section>
|
||||
<section>
|
||||
<title>Ranger Column Masking</title>
|
||||
<p>This release supports Ranger column masking, which hides sensitive columnar
|
||||
data in Impala query output. For example, you can define a policy that reveals
|
||||
only the first or last four characters of column data. Column masking is enabled
|
||||
by default. See <xref href="impala_authorization.xml#sec_ranger_col_masking"/>
|
||||
for details.</p>
|
||||
</section>
|
||||
<section>
|
||||
<title>BROADCAST_BYTES_LIMIT query option</title>
|
||||
<p>You can set the default limit for the size of the broadcast input. Such a limit
|
||||
can prevent possible performance problems.</p>
|
||||
<!--Add link to details after file is published.-->
|
||||
</section>
|
||||
<section>
|
||||
<title>Experimental Support for Apache Hudi</title>
|
||||
<p>In this release, you can use Read Optimized Queries on Hudi tables. See
|
||||
<xref href="impala_hudi.xml"/> for details. </p>
|
||||
</section>
|
||||
<section>
|
||||
<title>ORC Reads Enabled by Default</title>
|
||||
<p>Impala stability and performance have been improved. Consequently, ORC reads are now
|
||||
enabled in Impala by default. To disable, set <codeph>--enable_orc_scanner</codeph> to
|
||||
<codeph>false</codeph> when starting the cluster. See <xref href="impala_orc.xml"/> for
|
||||
details.</p>
|
||||
</section>
|
||||
<section>
|
||||
<title>Support for ZSTD and DEFLATE</title>
|
||||
<p>This release supports ZSTD and DEFLATE compression codecs for text files. See
|
||||
<xref href="impala_txtfile.xml#gzip"/> for details.</p>
|
||||
</section>
|
||||
</conbody>
|
||||
</concept>
|
||||
<concept rev="3.2.0" id="new_features_33">
|
||||
<title>New Features in <keyword keyref="impala33"/></title>
|
||||
<conbody>
|
||||
@@ -231,9 +410,9 @@ under the License.
|
||||
<title>Default File Format Changed to Parquet</title>
|
||||
<p>When you create a table, the default format for that table data is
|
||||
now Parquet.</p>
|
||||
<p>For backward compatibility, you can use the DEFAULT_FILE_FORMAT query
|
||||
option to set the default file format to the previous default, text,
|
||||
or other formats.</p>
|
||||
<p>For backward compatibility, you can use the
|
||||
<codeph>DEFAULT_FILE_FORMAT</codeph> query option to set the default
|
||||
file format to the previous default, text, or other formats.</p>
|
||||
</section>
|
||||
<section id="section_m1h_mnf_t3b">
|
||||
<title>Built-in Function to Process JSON Objects</title>
|
||||
|
||||
@@ -120,7 +120,8 @@ under the License.
|
||||
details.
|
||||
</p>
|
||||
|
||||
<p rev="2.0.0">You can also use text data compressed in the bzip2, deflate, gzip, Snappy, or
|
||||
<p rev="2.0.0">
|
||||
You can also use text data compressed in the bzip2, deflate, gzip, Snappy, or
|
||||
zstd formats. Because these compressed formats are not <q>splittable</q> in the way that LZO
|
||||
is, there is less opportunity for Impala to parallelize queries on them. Therefore, use
|
||||
these types of compressed data only for convenience if that is the format in which you
|
||||
|
||||
Reference in New Issue
Block a user