GitHub user gatorsmile opened a pull request:
https://github.com/apache/spark/pull/15136
[SPARK-17581] [SQL] Invalidate Statistics After Some ALTER TABLE Commands
### What changes were proposed in this pull request?
In the recent statistics-related work, our focus is on how to generate and
store the statistics. After `Analyze Table` commands, the statistics will not
be changed unless users run the command again. However, Hive behaves
differently. For example, `ALTER TABLE SET LOCATION` will invalidate the
statistics, including `numRows` and `rawDataSize`.
```
hive> describe formatted t2;
...
Location: hdfs://6b68a24121f4:9000/user/hive/warehouse/t2
Table Type: MANAGED_TABLE
Table Parameters:
COLUMN_STATS_ACCURATE true
numFiles 4
numRows 2
rawDataSize 2
totalSize 4
transient_lastDdlTime 1464590855
...
```
```
hive> alter table t2 set location
'hdfs://6b68a24121f4:9000/user/hive/warehouse/t1';
OK
Time taken: 0.113 seconds
```
```
hive> describe formatted t2;
...
Location: hdfs://6b68a24121f4:9000/user/hive/warehouse/t1
Table Type: MANAGED_TABLE
Table Parameters:
COLUMN_STATS_ACCURATE false
last_modified_by root
last_modified_time 1474178025
numFiles 4
numRows -1
rawDataSize -1
totalSize 4
...
```
This PR tries to fix the related issues.
### How was this patch tested?
Added test cases.
You can merge this pull request into a Git repository by running:
$ git pull https://github.com/gatorsmile/spark
invalidateStatsAfterAlterTable
Alternatively you can review and apply these changes as the patch at:
https://github.com/apache/spark/pull/15136.patch
To close this pull request, make a commit to your master/trunk branch
with (at least) the following in the commit message:
This closes #15136
----
----
---
If your project is set up for it, you can reply to this email and have your
reply appear on GitHub as well. If your project does not have this feature
enabled and wishes so, or if the feature is enabled but not working, please
contact infrastructure at infrastruct...@apache.org or file a JIRA ticket
with INFRA.
---
---------------------------------------------------------------------
To unsubscribe, e-mail: reviews-unsubscr...@spark.apache.org
For additional commands, e-mail: reviews-h...@spark.apache.org
