CODEWITHSUNDEEP
cassandracopyexport-to-csvnosql
Abhay Bh
Abhay Bh

Reputation: 53

How to Copy Selective Rows from Cassandra Tables?

I want to copy only selective rows and columns from a specific Cassandra table. How do I that?

I am able to copy complete tables in .csv format with the help of:https://docs.datastax.com/en/cql/3.1/cql/cql_reference/copy_r.html

But, how do I copy selective data only?

I tried referencing: Selective copy cassandra million rows data to external file AND Cassandra selective copy . But none of them work.

Upvotes: 0

Views: 2594

Answers (2)

Bigby
Bigby

Reputation: 331

You can specify which columns you would like to update. Say, if you 10 different columns but you want to copy only 3 of them then you specify like this 

COPY products (name, id, color) from 'products.csv';

The only constraint over here is the CSV files should contain the only 3 columns. I'd suggest you to make a copy of csv file and refactor it. You can easily do it in python using csv library.

Upvotes: 0

S. Stas
S. Stas

Reputation: 810

There is no built-in support for selective copy. You could either export the whole bunch of data and do filtering on the client side or use some Map-Reduce (or Spark) job otherwise to extract the data you need.

Upvotes: 0

Related Questions