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I'd suggest a key-value DBMS, but I throw this out there for interest's sake. Instead of performing INSERT & DELETE statements, only do UPDATEs. The table structure will be something like ID integer -- sequential ID Used boolean -- default FALSE Object -- whatever type is appropriate The object-holding column will be of fixed length to ...


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Redis doesn't support nested data structures, and specifically it doesn't support a Hash inside a Has :) You basically have a choice between two options: either serialize the internal Hash and store it in a Hash field or use another Hash key and just keep a reference to it in a field of the outer Hash.


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In your question you are using "SQL" and "relational" to mean the same thing. In the same way you can think of "NoSQL" as meaning "not relational" i.e. there is no primary key / foreign key concept; there is no "normalisation" enforced or implied; there is no real meaning of the words "table" or "column". To a key-value store all it knows about is a big ...


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NoSQL databases have faster writes mostly because they do not support cross-document transactions, ACID, and lack various data integrity constraint usually found in RDBMS. Neither of those things are trivial to support, especially in an environment where the database serves read/write requests from many users concurrently. Think of a typical table in a ...


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As you have multiple rows inside the JSON column, you need a function that returns a set. This can be done using the json_to_recordset() function: select j.* from json_test, json_to_recordset(json_data) as j(name text, country text, hobby text, address text, sex text); Because this is an anonymous record type, you must explicitly define each column. ...


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You didn't mention how the data comes in, but I would hazard a guess that it is through flat files. If this is the case, I worked at an order processing company that used Oracle for the back-end of the WMS we used. We regularly received 10 of millions of records a day. We used SQL loader scripts to load the data. The caveat to that is that the data needs to ...


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1) Consider how this information will be used. Will the owner want to try lots of ad hoc analysis and data exploration? Does your potential data store have tools or connection libraries that allow this? Will the user have to resort to writing Map and Reduce functions for every question posed? 2) Do you mean that the same question is on different ...


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Someone make this bench: http://mimdl.tumblr.com/post/115308901909/benchmarking-handlersocket-mysql-innodb-memcached Get Operation with HandlerSocket was completed in 1.20499610901 Sec, i.e; making 8,299 QPS (Queries per second) Get Operation with InnoDB Memcached Plugin was completed in .93115 seconds i.e; making 10,739 QPS Select Query for MySQL took ...


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Many NoSQL products have sharding built-in. The DBMS itself looks after storing a particular key range on a certain server and keeping redundant copies for high availability. Client connections are routed within the DBMS rather than in the application. Multi-server scale out becomes easy, at the cost of CAP compromises.


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Although Cassandra allows the definition of "columns" within a "table", these are much less strict than a relational database schema. As it says here different rows in the same column family do not have to share the same set of columns, and a column may be added to one or multiple rows at any time. In this world, the new value is only added to the ...


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I can't test this at the moment, but that's the basic format. You should change your date data type to ISO so it works easily with the below code: var lastWeek = new Date(); lastWeek.setDate(lastWeek.getDate() -7); db.messages.find({ "rep_header.share_date_2.$date": { $gte: lastWeek} } } );



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