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Showing posts from February, 2016

What is Avro Schema

Avro schema generally used to define the data schema for a record's value. This schema describes the fields allowed in the value, along with their data types. We can apply a schema to the value portion of an Oracle NoSQL Database record using Avro bindings. These bindings are used to serialize values before writing them, and to deserialize values after reading them. The usage of these bindings requires our applications to use the Avro data format, which means that each stored value is associated with a schema.

The use of Avro schemas allows serialized values to be stored in a very space-efficient binary format. Each value is stored without any metadata other than a small internal schema identifier, between 1 and 4 bytes in size. One such reference is stored per key-value pair. In this way, the serialized Avro data format is always associated with the schema used to serialize it, with minimal overhead. This association is made transparently to the application, and the internal schem…

Difference between key-value stores and key-value pairs

Difference between key-value stores and key-value pairs or
Difference between  Key-value stores  and document db or
Difference between Redias and mongoDb .


Key Values always Confusedmethat's why i decided to share my some short of experience, InNoSQL Databases KV Pair and KV Stores are different. Event they are related to different database vendors too.

Key-Value stores ; store keys value pairs  in buckets, exactly like a hash table data structure; where each key must be unique.  They are extremely fast for writing, and extremely fast for reading and updating. if you have the key.  They are slow on multiple updates and if you have to query the entire store.  You see Key-value stores used a lot as caching stores because of their fast reads.
eg: Redis, Riak, memcached, Azure's tablestore, etc

Document Stores ; store data in "documents", typically XML or JSON documents. They're typically schema-less, so each document can contain any data that you want them to have and yo…