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cassandra super column family

What is Supercolumn Family ? I currently load a Keyspace with a certain amount of SCFs. Note: Cassandra-3974 might introduce TTL for the column family, separate from column TTL. The structure is <>ProductCategory <>#ProductType <>#productCatId +subProdName +lenght +width The Counter column family holds distributed counters meant (of course) for distributed counting. Furthermore, applications can specify the sort order of columns within a Super Column or Simple Column family. Cassandra exposes two kinds of columns families, Simple and Super column families. :ttl - If specified this is the number of seconds after the insert that this value will be available. Both kinds of columns are name/value pairs, but a regular column stores a byte array value, and the value of a super column is a map of sub columns (which store byte array values). From cassandra definitive guide !! Super column family in cassandra. What is Supercolumn Family ? The following layout represents a row in a Super Column Family (SCF): ... As mentioned earlier, there is something called a “Super Column” in Cassandra. The structure is <>ProductCategory <>#ProductType <>#productCatId +subProdName +lenght +width I tried a lot many ways but I can't find the right way to get this done. These column families could be considered then as tables. Fetching all the 4 columns in the Super-Column 'address' cassandra> get Prototype.Supermaster['1']['address'] => (column=flat, value=CDS, RPG, timestamp=1286273243882000) => (column=city, value=chennai, timestamp=1286273287246000) => (column=area, value=velachery, timestamp=1286273267318000) => (column=apt, value=B-5C, timestamp=1286273186596000) … They are actually key-value pairs with values as columns. Cassandra. cassandra. Each SCF (Super Column Family) represents an entity. We've finally been able to upgrade our cluster to 2.0.11, after CASSANDRA-7188 being fixed. preload_row_cache − It specifies whether you want to pre-populate the row cache. To: ReplyTo: user@cassandra.apache.org Subject: create super column family for I am trying to create a super column family using Cli command. With the super column family i can retrieve a list of texts for a specific sector with only 1 request to cassandra. Tools Uses : 1) Apache-cassandra-2.1.6 2) eclipse version Luna 4.4.1. Simple Use Case : I have a CustomerList, this holds different customers. Thus, each key identifies a row of a variable number of elements. Each key has values as columns, and columns are grouped together into sets called column families. column_families: name: CFYaml column_type: Super compare_with: LongType compare_subcolumns_with: UTF8Type In both cases Subcolumn comparator was defined as UTF8Type but CF was created with subcomparatortype of LongType Tools Uses : 1) Apache-cassandra-2.1.6 2) eclipse version Luna 4.4.1. The Cassandra data model defines . John Grogan. One of the Cassandra key characteristics is that it only allows for a primary key to have multiple columns and HBase only comes with 1 column row keys and puts the responsibility of the row key design on the developers. share | improve this question | follow | edited Oct 21 '13 at 12:21. 2) A column family with a column family as a value of key. Column is a triplet := (name, value, timestamp). Whereas the Cassandra column families are predefined and hence, cannot be changed. Key store> column family > super column> column data structure in JSON (JavaScript Object Notation). Don’t use the Counter column family to generate surrogate keys. It groups all the columns used regularly as binds them in a single space. Let’s revise Cassandra Documented Shell Commands. Put slightly differently, a row in a super column family still contains columns, each of which then contains subcolumns. Super column families can be visualized as a column family within a column family. The system allows columns to be sorted either by time or by name. They are actually key–value pairs with values as columns. But I am not getting it. When specifying a super column family name inside a Deletion and a standard column family name in the mutations dictionary, we get a RuntimeException in the server and a TimedOutException on the client: Simple Use Case : I have a CustomerList, this holds different customers. options - Valid options are: :timestamp - Uses the current time if none specified. Data Types : Validators & Comparators; Indexes; Keyspace

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