Apache Avro™ 1.7.6; Documentation; Introduction; Schemas; Comparison with other systems. Introduction: Apache Avro™ is a data serialization system. Avro provides: Rich data structures. A compact, fast, binary data format. A container file, to store persistent data. Remote procedure call (RPC). Simple integration with dynamic languages. Code generation is not required to read or write data files nor to use or implement RPC protocols. Code generation as an optional optimization, only worth implementing for statically typed languages. Schemas Avro relies on schemas. When Avro data is read, the schema used when writing it is always present. This permits each datum to be written with no per-value overheads, making serialization both fast and small. This also facilitates use with dynamic, scripting languages, since data, together with its schema, is fully self-describing. When Avro data is stored in a file, its schema is stored with it, so that files may be processed later by any program. If the program reading the data expects a different schema this can be easily resolved, since both schemas are present. When Avro is used in RPC, the client and server exchange schemas in the connection handshake. (This can be optimized so that, for most calls, no schemas are actually transmitted.) Since both client and server both have the other’s full schema, correspondence between same named fields, missing fields, extra fields, etc. can all be easily resolved. Avro schemas are defined with JSON . This facilitates implementation in languages that already have JSON libraries. Comparison with other systems Avro provides functionality similar to systems such as Thrift, Protocol Buffers, etc. Avro differs from these systems in the following fundamental aspects. Dynamic typing: Avro does not require that code be generated. Data is always accompanied by a schema that permits full processing of that data without code generation, static datatypes, etc. This facilitates construction of generic data-processing systems and languages. Untagged data: Since the schema is present when data is read, considerably less type information need be encoded with data, resulting in smaller serialization size. No manually-assigned field IDs: When a schema changes, both the old and new schema are always present when processing data, so differences may be resolved symbolically, using field names. Apache Avro, Avro, Apache, and the Avro and Apache logos are trademarks of The Apache Software Foundation.

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I’VE GOT STANDARDS! I only fly ‘business’. Singer Jaguar snubbed last weekend’s Kilimanjaro Music Awards because the organisers could not afford to fly him business class to Dar es Salaam as he had demanded. Instead, Jaguar attended Grandpa Records boss Refigah’s wedding ceremony at Kibera Primary School, where he performed alongside other artistes like Lenny, Kenzo, V-Sita and Kenrazy. “If an artiste like Diamond can be flown business class to Kenya, I think the same can be done for me; I am well recognised in my field,” said Jaguar, who insisted that all East African artistes should be respected by music promoters.

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Full list of BAKE Kenya Blog Award Winners 2014. The 3rd edition of the Kenyan Blog Awards was held at the Intercontinetal Hotel. This time round, there were 17 blogs up for nomination. The Best County Blog and Best Health Blog were the new additions. The winners were picked through a process that started with submissions by bloggers, readers and virtually any person who has access to the internet in 17 categories. The submissions were then taken through a phase of trimming and pruning by independent judges who then gave us a list of 5 blogs per category for which readers would vote for. The shock for the evening came up when the winners for the Best Sports blog were announced. For the frst time since the inception of the awards there was a tie; michezoafrika.com and futaa.com emerged victorious. Below is the full list of BAKE Kenya Blog award winners for 2014. Best Technology Blog: techmoran.com, Best Photography Blog: benkiruthi.com, Best Creative Writing Blog: bikozulu.co.ke, Best Business Blog: bankelele.co.ke, Best Food Blog: pikachakula.com, Best Environmental/Agricultural Blog: farmingafrika.com, Best Fashion/Beauty/Hair/Style Blog: thisisess.com, Best Politics Blog: brainstorm.co.ke, Best New Blog: wendywahito.com, Best Corporate Blog: ihub.co.ke, Best Topical Blog: mummytales.com, Best Sports Blog (A tie): michezoafrika.com, futaa.com; Best Entertainment/Lifestyle Blog: ghafla.com, Best Travel Blog: safari254.com, Best Health Blog: 2;” href=”http://wambuiwaithaka.com/” target=”_blank”>wambuiwaithaka.com, Best County Blog: county-411.com, Best Kenyan Blog of the Year: bikozulu.co.ke

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