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I have been trying to see if I can have nested columns in a cassandra column family either super or normal. I have look all over and have not fully seen what I am looking for.

I am wanting to do something like this.

 `[{ firstname: "Me", 
     lastname: "Smith",
     HomeAddress: { Street: "1234 Any Place Dr"
                    ,State: "IL"
                    ,zip:  "62024"
                  }
  }]`

From the following post Create a Cassandra schema for a super column with metadata

I found something similar but it is not working the way I wanted to. 

create column family users                           
with comparator = UTF8Type
 and compression_options = { sstable_compression:SnappyCompressor, chunk_length_kb:64}
 and column_metadata = [
  { column_name: FirstName, validation_class : UTF8Type}
  { column_name: LastName, validation_class : UTF8Type},
  { column_name: FavStore, validation_class : IntegerType}
 , { column_type: super, column_name: HomeAddress } 
 ];

Here is my code that shows how I created my column family.

It creates it but then if I put the address in like the JSON example above it does not seem to work.

Here is my output when I do a list from the cli.

RowKey: 646f68616c6c => (column=FavStore, value=59580595188280, timestamp=1330696438) => (column=Favorites, value=HASH(0x3618bc0), timestamp=1330696438) => (column=FirstName, value=Me, timestamp=1330696438) => (column=HomeAddress, value=HASH(0x3618b30), timestamp=1330696438) => (column=LastName, value=Smith, timestamp=1330696438)

When I try and pull out the values from Home Address I get nothing. It appears that it is empty. I pulled it from some perl code and the Hash tells me that it is blank.

I am wondering if this is even possible and if it is not what is the best approach to add a sub column to a column family. Or am I just barking up the wrong tree.

Any info would be greatly appreciated.

Community
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Dan O'Halloran
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1 Answers1

2

You are trying to mix normal columns and super columns. Cassandra requires that all columns in a column family are either normal columns or super columns. Instead of trying to use a super column you could do one of the following:

  • Split the home address column up into 3 columns: address_street, address_state, address_zip
  • Store the components of the address in one column using your favorite serialization format (json, protocol buffers, etc.)
psanford
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