Type classes in Scala
I am going to show you how I went about solving how to persist instances in Cassandra, using Hector, in the function insert(instance) in Scala. To work out how these instances are going to be persisted, I shall use type classes. More than just the code, I will explain & show every step of my design.
Crash course in Cassandra
Cassandra is a schema-free database; to understand it, here are the most important concepts and their loose mapping to the relational databases counterparts:
1 keyspace – schema; database
2 column family – table, with key and rows
3 key – primary key
4 row – collection of columns; the rows in the column family may have completely different columns
5 column – column
When inserting data into Cassandra, we must be able to serialize the data to be inserted. To do that, we must know the key type and the names and types of all columns.
Crash course in Cassandra
Cassandra is a schema-free database; to understand it, here are the most important concepts and their loose mapping to the relational databases counterparts:
1 keyspace – schema; database
2 column family – table, with key and rows
3 key – primary key
4 row – collection of columns; the rows in the column family may have completely different columns
5 column – column
When inserting data into Cassandra, we must be able to serialize the data to be inserted. To do that, we must know the key type and the names and types of all columns.
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