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impala Error for count(*)

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impala Error for count(*)

New Contributor

Hi, I installed CM5beta2, CDH5beta2 and impalad version 1.2.3-cdh5.0.0-beta-2 RELEASE. I tried the Imapa tutorial and found some weird things.

 

I created an external table using the following command:

create EXTERNAL TABLE tab1 ( id INT, col_1 BOOLEAN, col_2 DOUBLE, col_3 TIMESTAMP ) ROW FORMAT DELIMITED FIELDS TERMINATED BY ',' LOCATION '/tmp/data/tab1';

 

and in the impala-shell, I ran the simple query:

[CHD2:21000] > select * from tab1;
Query: select * from tab1
+----+-------+------------+-------------------------------+
| id | col_1 | col_2 | col_3 |
+----+-------+------------+-------------------------------+
| 1 | true | 123.123 | 2012-10-24 08:55:00 |
| 2 | false | 1243.5 | 2012-10-25 13:40:00 |
| 3 | false | 24453.325 | 2008-08-22 09:33:21.123000000 |
| 4 | false | 243423.325 | 2007-05-12 22:32:21.334540000 |
| 5 | true | 243.325 | 1953-04-22 09:11:33 |
+----+-------+------------+-------------------------------+
Returned 5 row(s) in 12.85s

 

However, when I ran the select count(*) from tab1, only once I can get the result.

CHD2:21000] > select count(*) from tab1;
Query: select count(*) from tab1
+----------+
| count(*) |
+----------+
| 5 |
+----------+
Returned 1 row(s) in 2.51s

 

For the rest, the query is hanging and finally throw the timeout exception.

 

[CHD2:21000] > select count(*) from tab1;
Query: select count(*) from tab1
ERROR: Resource reservation request exceeded timeout of 300000ms.
Warning: The following tables are missing relevant table and/or column statistics leading to inaccurate resource estimates:
default.tab1

 

 

1 REPLY 1

Re: impala Error for count(*)

Explorer

Hi Johnson -

 

Sorry if you've still having this issue. First, have you had a chance to upgrade to the newest version of Impala released with CDH5 (1.3.0)? If you have, and you're still having the issue, please let me know. 

 

I am curious to get the query profile from the SELECT COUNT(*), as well as the Impala daemon logs from the coordinator node that you're submitting the query to (/var/log/impalad). Both links in this message should help with finding the appropriate logs / profile. 

 

Other questions for you, is this cluster using YARN with LLAMA? Does restarting Impala fix the issue? 

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