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IMPALA-10475: [DOCS] elaborate SYNC_DDL option

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call out that SYNC_DDL applies to all filesystem-based tables

Change-Id: I3f1bfce8430c681515101d00cabf9d70ae52e5ec
Reviewed-on: http://gerrit.cloudera.org:8080/17027
Tested-by: Impala Public Jenkins <impala-public-jenkins@cloudera.com>
Reviewed-by: Tim Armstrong <tarmstrong@cloudera.com>
This commit is contained in:
Shajini Thayasingh
2021-02-05 10:43:53 -08:00
committed by Tim Armstrong
parent a3f441193d
commit 81d5377c27
1 changed files with 7 additions and 7 deletions
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14
docs/topics/impala_sync_ddl.xml
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@@ -46,13 +46,13 @@ under the License.
you quickly switched to another node, such as by issuing a subsequent query through a load-balancing proxy.)
</p>
<p>
Although <codeph>INSERT</codeph> is classified as a DML statement, when the <codeph>SYNC_DDL</codeph> option
is enabled, <codeph>INSERT</codeph> statements also delay their completion until all the underlying data and
metadata changes are propagated to all Impala nodes. Internally, Impala inserts have similarities with DDL
statements in traditional database systems, because they create metadata needed to track HDFS block locations
for new files and they potentially add new partitions to partitioned tables.
</p>
<p> Although <codeph>INSERT</codeph> is classified as a DML statement, when the
<codeph>SYNC_DDL</codeph> option is enabled, <codeph>INSERT</codeph> statements also delay
their completion until all the underlying data and metadata changes are propagated to all
Impala nodes and this option applies to all filesystem-based tables. Internally, Impala
inserts have similarities with DDL statements in traditional database systems, because they
create metadata needed to track HDFS block locations for new files and they potentially add
new partitions to partitioned tables. </p>
<note>
Because this option can introduce a delay after each write operation, if you are running a sequence of