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5

Welcome to database hell! NoSQL is often championed as a solution to these types of applications. However, your problem here is clearly that the programmers have no idea what they are doing. Furthermore, it looks like your management is afraid of change, or unwilling to take the hard decisions which you correctly list and which are likely to fix the root ...


5

Option 4: Class Table Inheritance This is a design technique used to implement a class/subclass situation. In this situation, attributes often apply only to one subclass, and not to all rows in the table. Visit the tag of the same name over in SO to see a bunch of relevant questions and answers. This has the advantage eliminating NULLS (mostly), ...


4

It's really too early to tell from what you've described - not enough detailled information. There are those who say (probably correctly) that NoSQL systems can update rapidly - even more rapidly than RDBMS technology. However, that speed comes at a price (no SQL/poor indexing) - this is the ONE thing that people should realise about NoSQL. It does have ...


4

cqlsh -k mykeyspace -e 'COPY fromTable(columnNames) TO STDOUT' | head -n -1 | cqlsh -k mykeyspace -e 'COPY toTable(columnNames) FROM STDIN'


2

Did you take a look at sstableloader http://www.datastax.com/documentation/cassandra/2.0/cassandra/tools/toolsBulkloader_t.html ?


2

I would recommend using InnoDB memcached over Handlersocket. The advantage of InnoDB memcached is that: It uses a standard memcached protocol, with drivers available for many programming languages. It does not automatically allow access to all tables in your database, but instead tables 'opt-in' via a mapping containers table. It has a stated support ...


2

To monitor - OpsCenter: http://www.datastax.com/what-we-offer/products-services/datastax-opscenter To query - DevCenter: http://www.datastax.com/what-we-offer/products-services/devcenter


2

The data structure that maintains the bin information grows monotonically during the life of the process. The only way to remove Bin[s] from Aerospike is to first remove the bin from all records containing it followed by a rolling restart of the cluster. You can find documentation on using scan here And see DeleteBin.java in aerospike/examples for how to ...


2

MongoDB's dynamic schema supports different fields for documents within the same collection, so there is no strict requirement for all documents to have an active field. The main consideration here will be how that affects your application logic; it may be simpler to have an explicit field present and check the value. If you have an index on a field, ...


2

My largest obstacle right now with Cassandra are the no-join, no order by (since everything is ordered by key for you), and mass update. If your current data structure depends on joins (or aggregation) to pull off the queries you need you won't find a nosql option that includes these. You do have some options: Consider reviewing your current data ...


1

Using an RDBMS is fine, but the sticky part is how to store the parameters needed to render each type of question. I would caution against having separate table definitions (or lots of type-specific columns) for each type of question. While these details (such as the list choices for a multiple-choice question) can be seen through a relational lens, it ...


1

Just execute on shell "use dbname" When you insert the first document on any collection you will see the db with "show dbs"


1

In Cassandra you need to take a query-based modeling approach. In your case, I would create a similarly-structured query table like this: CREATE TABLE topicbyuser ( topic_id text, user_id text, event_time timestamp, data text, PRIMARY KEY (user_id,event_time), ) WITH CLUSTERING ORDER BY (event_time DESC); And then, if you wanted to ...


1

As NoSQL databases typically do not support joins, they expect you to store the data in de-normalized form. (So, throw the codd normalization rule book away. Just kidding). In this case, the thrid table better have the values duplicated something like (orderid, ordertime, [itemnames], waitername, orderserviced yes/no, servicetime, ...). itemnames can be a ...


1

Neo4j is a schema-optional graph database. You could choose to enforce a full schema and reap the benefits.


1

Use the maxmemory to set a limit to how much your Redis database can grow too. Failing to do so, Redis will grow until the OS will kill it once memory is exhausted (per your current experience). The usage of maxmemory should be coupled with maxmemory-policy - you can choose from different eviction policies depending on your use case's requirements. For ...


1

As usual in similar cases, I would strongly recommend that you look at Open Source solutions - well before the design phase. EVEN if you are doing something truly radical, one can always learn by standing on the shoulders of giants. I have worked as a student on the OpenEHR project, so this interests me. It's been a while, but I would start by looking here, ...


1

You can also set the bin to null to delete it. http://www.aerospike.com/docs/client/java/usage/kvs/write.html#delete-a-bin


1

Ok, I found the solution, I have to use the reduce function for that, like: function(keys, values, rereduce){ var result = null; var orders = [] for(var i =0; i< values.length; i++){ if(values[i].type=='customer') result = values[i]; else{ orders.push(values[i]) } } result.orders = orders; return result; }


1

Normally you should never do so because other revisions may be deleted after compacting the database. You should include all necessary fields to recompose(reprint) the invoice in the invoice document, like: product description, product price, total, and so on. This is the same if you would store invoices in a rdbms.


1

In general, clustered-NoSQL databases offer you better horizontal scalability. So, as you scale you can get higher capacity (both memory & compute power) by simply adding new nodes. So, it will be a good insurance for the future. When it comes to ACID properties, NoSQL databases offer flexibility. So, it boils down to how much ACIDness you want and how ...


1

You can run a --repairDatabase for that node: mongod --repair --repairpath <repair_path> Keep in mind that the repair path should have at least as your data size free disk space. (if you have 100GB, the repair path should have at least 100GB free also. That should take care of problems of that sort. Also, in the future if anything of some sort ...


1

There's two parts to this question: Where should the data be persisted permanently? Let's hold off on that part until we answer the second one, which is much more important: Where should the clients query to check for vulnerabilities? A caching layer. Your clients should never hit the underlying data store first. There's not a need for atomic ...


1

I think your first idea is better. The second way, as you state, is how you would model the data in an RDBMS. If you're going to use MongoDB for fun, you might as well explore the fact that it has a different data model, and structure your collections accordingly. While I'm sure performance is not going to be an issue for the scale of this project, ...


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Team { id : id, name : String, teamLink : String, username : String, userLink : String, league : Number, Stats : [{ desc : String, value : String, globalRank : Number, globalPts : Number, divRank : Number, divPts : Number, year:Number }] } League { id : Number, ...


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The search is made on the server host where the database service is installed. And you will only get the result set sent to you. It would make no sense your client to make this, as your client is just an interface that allows your to interact with your database. This is available for all databases.


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I would not recommend doing automatic migrations from any relational databases (or other that differs in logic) to MongoDB. Of course it can be done, but the database performance might not be (and will most probably not be) good. Now, answering your questions directly: 1) what do you mean by MySQL parameters? 2) Check the official docs page about the ...


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Have you tried Helenos: https://github.com/tomekkup/helenos It seems good



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