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https://issues.apache.org/jira/browse/PHOENIX-2514?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15063801#comment-15063801
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Sumit Nigam commented on PHOENIX-2514:
--------------------------------------
Hi James,
I have Phoenix from https://github.com/apache/phoenix
If the fix for PHOENIX-2125 made it to git above, then I must have the fix
because the issue got resolved sometime in July and I downloaded this distro in
Sept this year.
Also, the bug shows up only when #of records is high (> 100K) which is why it
may not have shown up in your test. There really is no unit test here. The same
queries work perfectly until volume in table becomes high and gets distributed
to say, 3 region servers.
As you suggested, I will give it a try with 4.6.
Thanks,
Sumit
> Even with ORDER BY clause the LIMIT does not work correctly with salted
> tables containing many records.
> -------------------------------------------------------------------------------------------------------
>
> Key: PHOENIX-2514
> URL: https://issues.apache.org/jira/browse/PHOENIX-2514
> Project: Phoenix
> Issue Type: Bug
> Affects Versions: 4.5.1
> Environment: HBase-0.98.14
> Reporter: Sumit Nigam
> Priority: Critical
> Labels: LIMIT, hbase, phoenix, salted
> Attachments: data.zip
>
>
> A query such as SELECT CURRENT_TIMESTAMP FROM TBL ORDER BY CURRENT_TIMESTAMP
> DESC LIMIT 1 does not really return the MAX(CURRENT_TIMESTAMP). The table is
> salted and has 200272 records.
> select current_timestamp from TBL order by current_timestamp desc limit 1;
> +------------------------------------------+
> | CURRENT_TIMESTAMP |
> +------------------------------------------+
> | 1448815328556 |
> +------------------------------------------+
> select max(current_timestamp) from TBL;
> +------------------------------------------+
> | MAX("CURRENT_TIMESTAMP") |
> +------------------------------------------+
> | 1449732792090 |
> +------------------------------------------+
> The results are different. MAX is of course, returning the right record.
> The above query is one example. There are other queries which also seem to be
> returning incorrect record with ORDER BY and LIMIT.
> Is this also correct that when there is a WHERE clause limiting the number of
> projected records, then LIMIT seems to work fine? I seem to be noticing that
> also.
> The table DDL is:
> CREATE TABLE IF NOT EXISTS TBL
> (CURRENT_TIMESTAMP BIGINT NOT NULL, ID VARCHAR(96), CURR_EXDOC VARCHAR,
> CURR_CHECKSUM VARCHAR(32), SUMMARY VARCHAR,
> CONSTRAINT PK PRIMARY KEY(CURRENT_TIMESTAMP, ID))
> BLOCKCACHE=FALSE, COMPRESSION=SNAPPY, SALT_BUCKETS=8
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