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From Jimmy Lin <y2klyf+w...@gmail.com>
Subject get all row keys of a table using CQL3
Date Wed, 24 Jul 2013 05:18:09 GMT
hi,
I want to fetch all the row keys of a table using CQL3:

e.g
select id from mytable limit 9999999


#1
For this query, does the node need to wait for all rows return from all
other nodes before returning the data to the client(I am using astyanax) ?
In other words, will this operation create a lot of load to the initial
node receiving the request?


#2
if my table is big, I have to make sure the limit is set to a big enough
number, such that I can get all the result. Seems like I have to do a
count(*) to be sure....
is there any alternative(always return all the rows)?

#3
if my id is a timeuuid, is it better to  combine the result from couple of
the following cql to obtain all keys?
e.g
select id from mytable where id t < minTimeuuid('2013-02-02 10:00+0000')
limit 20000
+
select id from mytable where id t > maxTimeuuid('2013-02-02 10:00+0000')
limit 20000

thanks

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