[IMPALA-4776] Table stats removed when setting TBLPROPERTIES

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Duplicate
• Affects Version/s: Impala 2.6.0
• Component/s: Catalog
• Environment: CDH 5.82 running impala2.6.0-cdh5.8.2
• Assignee: Unassigned
• Reporter: Nicholas Brenwald
• Created: 17/Jan/17 21:53
• Updated: 17/Jan/17 23:38
• Resolved: 17/Jan/17 23:38

Description

Possible duplicate of IMPALA-4767

Table stats seem to be removed when setting table properties.

To reproduce:
Create a table with a single column.

[impala:21000]> create table t(c int);

Insert 1 row of data:

[impala:21000]> insert into t values (1);

Compute stats:

[impala:21000]> compute stats t;

Running show table stats shows the value of 1 for #Rows:

[impala:21000] > show table stats t;
Query: show table stats t
+-------+--------+------+--------------+-------------------+--------+-------------------+--------------------------------------------------------+
| #Rows | #Files | Size | Bytes Cached | Cache Replication | Format | Incremental stats | Location                                               |
+-------+--------+------+--------------+-------------------+--------+-------------------+--------------------------------------------------------+
| 1     | 1      | 2B   | NOT CACHED   | NOT CACHED        | TEXT   | false             | hdfs://.../t |
+-------+--------+------+--------------+-------------------+--------+-------------------+--------------------------------------------------------+

Now set an arbitrary table property:

impala:21000> ALTER TABLE t SET TBLPROPERTIES ('field' = 'value');

But we now seem to have lost the table level stats. Show table stats in impala now says -1 for #Rows:

[impala:21000] > show table stats t;
Query: show table stats t
+-------+--------+------+--------------+-------------------+--------+-------------------+--------------------------------------------------------+
| #Rows | #Files | Size | Bytes Cached | Cache Replication | Format | Incremental stats | Location                                               |
+-------+--------+------+--------------+-------------------+--------+-------------------+--------------------------------------------------------+
| -1    | 1      | 2B   | NOT CACHED   | NOT CACHED        | TEXT   | false             | hdfs://.../t |
+-------+--------+------+--------------+-------------------+--------+-------------------+--------------------------------------------------------+