Samarth,
Created a table with three columns
0: jdbc:phoenix:localhost> create table employees_2015_phoenix (id varchar
primary key, first_name varchar, last_name varchar)
DEFAULT_COLUMN_FAMILY='default' SPLIT ON ('10', '20', '30', '40');
Loaded data from a csv file
[phoenix_user@<hostname> bin]$ ./psql.py -t EMPLOYEES_2015_PHOENIX
<zookeeper_hostname> customers.csv
csv columns from database.
CSV Upsert complete. 100000 rows upserted
Time: 14.52 sec(s)
Explain query came out this way.
0: jdbc:phoenix:localhost> EXPLAIN SELECT * FROM EMPLOYEES_2015_PHOENIX LIMIT
1000;
+------------+
| PLAN |
+------------+
| CLIENT PARALLEL 25-WAY FULL SCAN OVER EMPLOYEES_2015_PHOENIX |
| SERVER FILTER BY PageFilter 1000 |
| SERVER 1000 ROW LIMIT |
| CLIENT 1000 ROW LIMIT |
+------------+
Thank you for stepping in to help me with my question.
Prasanth
From: Samarth Jain [mailto:[email protected]]
Sent: Friday, May 15, 2015 11:19 AM
To: [email protected]
Subject: Re: Phoenix's behavior when applying limit to the query
Prasanth,
To help us answer you better please let us know your table schema. Also what
does EXPLAIN select * from <phoenix_table_name> limit 1000; tell you?
-Samarth
On Friday, May 15, 2015, Chagarlamudi, Prasanth
<[email protected]<mailto:[email protected]>>
wrote:
Hello,
I would appreciate if someone could help with my question regarding pheonix's
functionality.
Created a phoenix table and inserted 100,000 records(assume these are
spread across different regions region servers).
Now, when I issue a select query with a limit n..something like this
select * from <phoenix_table_name> limit 1000;
What would be phoenix's behavior?
-Does it read the all the data(from all the region servers) on
side server side, then apply limit to dataset and send the 1000 records to the
client?
or
-Does it bring all the data set to the client and then apply
the limit?
Thanks in advance
Prasanth Chagarlamudi
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