Category Archives: Cassandra
Apache Cassandra Secondary Indices
How are Secondary Indices really stored ? This is based on the article from Datastax found here; https://www.datastax.com/blog/2016/04/cassandra-native-secondary-index-deep-dive Let’s just create a simple table
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CREATE TABLE customer ( id int PRIMARY KEY, city text, name text ) |
Or visualized as a table : Column Type Key id int Primary Key city text name … Continue reading
UDF/User Defined Functions in Cassandra 3.x
I was just playing around with Cassandra WRITETIME and thought it was somewhat difficult to figure out the date / timestamp of a number like this (microseconds since EPOC) 1470645914253000. So in my example it looked like this
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cqlsh:bth> select id, writetime(dateofbirth) from bth.employee; id | writetime(dateofbirth) ----+------------------------ 1 | 1470645914253000 2 | 1470645977177000 7 | 1470948508799001 3 | 1470645977178000 (4 rows) cqlsh:bth> |
So … Continue reading
Cassandra set the writetime explicitly with a PreparedStatement
This is a quick one, I wanted to set the writetime of a row explicitly when I populate the database for testing purposes. We use the writetime of a column to filter them out. It required some looking around to … Continue reading