Vihang Karajgaonkar has uploaded this change for review. ( 
http://gerrit.cloudera.org:8080/17521


Change subject: IMPALA-10700: Add query options to skip deleting stats
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IMPALA-10700: Add query options to skip deleting stats

When a truncate table command is issued, in case of
non-transactional tables, the table and column statistics for the table
are also deleted by default. This can be a expensive operation
especially when many truncate table commands are running concurrently.
As the concurrency increases, the response time from Hive metastore
slows down the delete table and column statistics RPC calls.

In cases where truncate operation is to used to remove the existing
data and then reload new data, it is likely that users will compute
stats again as soon as the new data is reloaded. This would overwrite
the existing statistics and hence the additional time spent by
the truncate operation to delete column and table statistics becomes
unnecessary.

To improve this, this change introduces 2 new query options:
1. SKIP_DELETE_TABLE_STATS
2. SKIP_DELETE_COLUMN_STATS

As the names suggest, when these query options are set to true or 1,
a truncate operation will not delete the respective statistics for the
table.

Testing:
Modified truncate-table.test to include variations of these query
options and making sure that the statistics are deleted or skipped
from deletion after truncate operation.

Change-Id: I9400c3586b4bdf46d9b4056ea1023aabae8cc519
---
M be/src/service/query-options.cc
M be/src/service/query-options.h
M common/thrift/ImpalaService.thrift
M common/thrift/JniCatalog.thrift
M common/thrift/Query.thrift
M fe/src/main/java/org/apache/impala/service/CatalogOpExecutor.java
M fe/src/main/java/org/apache/impala/service/Frontend.java
M testdata/workloads/functional-query/queries/QueryTest/truncate-table.test
8 files changed, 424 insertions(+), 25 deletions(-)



  git pull ssh://gerrit.cloudera.org:29418/Impala-ASF refs/changes/21/17521/1
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Gerrit-Project: Impala-ASF
Gerrit-Branch: master
Gerrit-MessageType: newchange
Gerrit-Change-Id: I9400c3586b4bdf46d9b4056ea1023aabae8cc519
Gerrit-Change-Number: 17521
Gerrit-PatchSet: 1
Gerrit-Owner: Vihang Karajgaonkar <[email protected]>

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