Cassandra selective copy

cassandra cql cql3
Dhamodaran picture Dhamodaran · Aug 26, 2013 · Viewed 9.5k times · Source

I want to copy selected rows from a columnfamily to a .csv file. The copy command is available just to dump a column or entire table to a file without where clause. Is there a way to use where clause in copy command?

Another way I thought of was,

Do "Insert into table2 () values ( select * from table1 where <where_clause>);" and then dump the table2 to .csv , which is also not possible.

Any help would be much appreciated.

Answer

Amine CHERIFI picture Amine CHERIFI · Apr 16, 2015

There are no way to make a where clause in copy, but you can use this method :

echo "select c1,c2.... FROM keySpace.Table where ;" | bin/cqlsh > output.csv

It allows you to save your result in the output.csv file.

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