in-memory

MySQL Cluster with MySQL innoDB persistent store

We are working on a database solution for a high available (5 9s) application with high performance and data consistency needs. We are planning to use MySQL Cluster as the primary in-memory datastore backed up by a secondary innoDB MySQL datastore for persistent storage. The proposed approach is that the online application will only inte...

In-memory DBMS's for unit testing

I am looking for satisfactory options for unit testing my .NET DAL classes; since they're DAL classes, they access the database directly using ADO.NET. Presently I use an instance of a MSSQL database for the testing, but was wondering what faster options there are---since unit tests need to run as quickly as possible, an in-memory solut...

Serialize in memory object with C#

I've got a program that picks up some code from script files and compiles it. And It works fine. The problem is: in the scripts I declare a couple of classes and I want to serialize them. Obviously the C# serializer (xml and binary) doesn't like to serialize and the de-serialize object defined in a in-memory assembly. I prefer to don't...

Is it possible to generate and return a ZIP file with App Engine?

I have a small project that would be perfect for Google App Engine. Implementing it hinges on the ability to generate a ZIP file and return it. Due to the distributed nature of App Engine, from what I can tell, the ZIP file couldn't be created "in-memory" in the traditional sense. It would basically have to be generated and and sent i...

Is there an existing DataSource that takes its data from DataTable in ASP.NET?

I'm making an ASP.NET Web Forms application. I would like to get a DataSource which takes its data from a DataTable, and this table is persisted among requests (preferably in session, not ViewState). The idea is that there is a need for some fairly complex forms where there are several gridviews in each of them. All the gridviews have t...

In Memory Database

I'm using SqlServer to drive a WPF application, I'm currently using NHibernate and pre-read all the data so it's cached for performance reasons. That works for a single client app, but I was wondering if there's an in memory database that I could use so I can share the information across multiple apps on the same machine. Ideally this wo...

Key-Value Stores vs. RDBMs vs. "Cloud" DBs (SDB)

I'm comfortable in the MySQL space having designed several apps over the past few years, and then continuously refining performance and scalability aspects. I also have some experience working with memcached to provide application side speed-ups on frequently queried result sets. And recently I implemented the Amazon SDB as my primary ...

How do I get make the in_memory adapter of the the ruby library DataMapper to save the model's id properly?

This regards the ruby ORM library DataMapper. This wiki describes how to use the in_memory adapter for DataMapper. The proper database adapters saves an incrementing, unique id on each model instance - in_memory doesn't seem to do that as shown by the following snippet: require 'rubygems' require 'dm-core' DataMapper.setup(:in_memory,...

Using Sqlite InMemory DB for unittesting MSSQL-DB

Hallo, i am trying to implent this solution NHibernate-20-SQLite-and-In-Memory-Databases the only problem is that we have hbm's like this <class name="aTable" table="[dbo].[aTable]" mutable="true" lazy="false"> with [dbo] in the tablename because we are working with mssql and this does not work with Sqlite. i found also this postin...

How do I open an in-memory database file into sqlite3

I'm on a system with no access to disk. My C program has in memory the contents of a valid, small, sqlite3 file (received over the network). I would like to use sqlite3's C API to open and access this file (read-only is fine). How do I do this? I know I can create an empty in-memory database with sqlite3_open(":memory:", &foo) but is...

How can I pull objects out of hibernate and into memory. I'm hitting session problems.

Hi, I have a rather enormous project in which I'm trying to retrofit in-memory data. Essentially, I have a big collection of objects which contain primitives and other objects which exist in hibernate. Large sections of non-dao code rely on lazy-loading through hibernate to hydrate objects on the fly. However, since everything exists in ...

Has anyone published a detailed comparison between different in-memory RDBMSs?

There are quite a few independent and not-so-independent studies comparing traditional RDBMSs but I haven't managed to find any good material on in-memory databases. I am primarily interested in ones specialized for OLTP. So far, I managed to find generic white papers on TimesTen and MySQL Cluster, but I have yet to see a head-to-head c...

Handling massive in memory objects in .NET

hey guys, here's the issue, Essentially, I have a very large List containing in turn relatively large Dictionaries So basically, I have a very big in memory collection. I then serialize this collection manually to XML, and send it over http. needless to say, the XML is too large, sometimes so large I get an OutOfMemory exception befor...

SubSonic .Filter() in memory filter

hi guys, i'm having some issues getting the .Filter() method to work in subsonic, and i'm constantly getting errors like the one below: Exception Details: System.NullReferenceException: Object reference not set to an instance of an object. Line 36: bool remove = false; Line 37: System.Reflec...

C++ distributed programming

Is there any library for distributed in-memory cache, distributed tasks, publish/subscribe messaging? I have used Hazelcast in Java, I would like something similar. I know that Memcached is an in-memory cache and even distributed, but it is missing the messaging and remote task. I just need something to coordinate a cluster of server w...

Achieving Fast Lookups for a Large Dataset: MySQL MEMORY(HEAP), Memcached, or something else

Currently working on a project that is centered around a medical nomenclature known as SNOMED. At the heart of snomed is are three relational datasets that are 350,000, 1.1 mil, and 1.3 mil records in length. We want to be able to quickly query this dataset for the data entry portion where we would like to have some shape or form of auto...

Load SQLite database from remote SQL Server?

I'm using SQLite ADO.NET in my project so that I can unit test using an in-memory database. I want a copy of my real database but it is across the server. From what I've read, it looks like I have to specify ":memory" for the data source for the SQLite connection string. My problem is that I don't even know if it's possible to load a ...

In memory 'list appender' for log4j

Is there an appender for log4j that only stores a list of the logging events (to be used in unit tests, to verify no error logs were written) ? ...

Does an in-memory database also have a filesystem component?

I'm working with Datamapper which allows you to specify either a path to a database file on your system or simply the string "memory" and then an "in-memory" database is used. However, I have no idea what this means. Is an "in-memory" database purely memory-based or does it get serialized to the filesystem at some point? What's the b...

Using SQL statements to query in-memory objects

Suppose I have a collection of C++ objects in memory and would like to query them using an SQL statement. I’m willing to implement some type of interface to expose the objects’ properties like columns of a database row. Is there a library available to accomplish this? In essence, I’m trying to accomplish something like LINQ without usi...