in-memory-database

sqlite:How to use in memory

安稳与你 提交于 2019-11-30 22:53:50
I am trying to store my data in memory here is what i have right now //sq lite driver Class.forName("org.sqlite.JDBC"); //database path, if it's new data base it will be created in project folder con = DriverManager.getConnection("jdbc:sqlite:mydb.db"); Statement stat = con.createStatement(); stat.executeUpdate("drop table if exists weights"); //creating table stat.executeUpdate("create table weights(id integer," + "firstName varchar(30)," + "age INT," + "sex varchar(15)," + "weight INT," + "height INT," + "idealweight INT, primary key (id));"); Now where should i put this statement[ ":memory:

sqlite:How to use in memory

僤鯓⒐⒋嵵緔 提交于 2019-11-30 17:47:56
问题 I am trying to store my data in memory here is what i have right now //sq lite driver Class.forName("org.sqlite.JDBC"); //database path, if it's new data base it will be created in project folder con = DriverManager.getConnection("jdbc:sqlite:mydb.db"); Statement stat = con.createStatement(); stat.executeUpdate("drop table if exists weights"); //creating table stat.executeUpdate("create table weights(id integer," + "firstName varchar(30)," + "age INT," + "sex varchar(15)," + "weight INT," +

Neo4j: is it a in-memory graph database?

不羁岁月 提交于 2019-11-30 17:45:00
问题 I have worked with bit older version of Neo4j i.e. 1.8.x. both embedded and REST mode . but I never heard that it store data in-memory. Recently I've been through Neo4j page which says 3 different type of access to neo4j viz: neo4j server i.e. REST mode embedded mode in-memory How Neo4J works with data in-memory ? and when it was implemented ? was it there from older version i.e. 1.8.x ? or just added in newer version ? any additional changes required in configuration such as Spring data

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

拟墨画扇 提交于 2019-11-30 05:19:24
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 comparison. There are other alternatives (e.g. from IBM), but there's even less easily available material. The information is scattered all over the web, but here's what I found out: Introduction to database benchmarking The first thing that you need to do is

How to shutdown Derby in-memory database Properly

纵然是瞬间 提交于 2019-11-30 03:35:24
I'm using derby as an embedded database. Furthermore, I'm using it's in-memory database option for my unit tests. What I can't figure out is how to properly shut down (A quick look at the code) the Derby database. I beleive I have it working for a standard database but I'm getting different exceptions when attempt similar code on a in-memory database. I'm going to omit details, I'll add them if other feel are needed. Basically, I'm trying to shut down my database in these two fashions where my in-memory database is consistently called "eh": DriverManager.getConnection("jdbc:derby:memory:eh

Why Spark SQL considers the support of indexes unimportant?

和自甴很熟 提交于 2019-11-29 22:55:30
Quoting the Spark DataFrames, Datasets and SQL manual : A handful of Hive optimizations are not yet included in Spark. Some of these (such as indexes) are less important due to Spark SQL’s in-memory computational model. Others are slotted for future releases of Spark SQL. Being new to Spark, I'm a bit baffled by this for two reasons: Spark SQL is designed to process Big Data, and at least in my use case the data size far exceeds the size of available memory. Assuming this is not uncommon, what is meant by "Spark SQL’s in-memory computational model"? Is Spark SQL recommended only for cases

Simple and reliable in memory database for fast java integration tests with support for JPA

浪尽此生 提交于 2019-11-29 05:44:24
My integration tests would run much faster if I used in-memory-database instead of PostgreSQL. I use JPA (Hibernate) and I need an in-memory-database that would be easy to switch to using JPA, easy to setup, and reliable. It needs to support JPA and Hibernate (or vice verse if you will) rather extensively since I have no desire to adopt my data access code for tests. What database is the best choice given requirements above? For integration testing , I now use H2 (from the original author of HSQLDB) that I prefer over HSQLDB. It is faster (and I want my tests to be as fast as possible), it has

Alternative to the TimesTen in memory database [closed]

蹲街弑〆低调 提交于 2019-11-29 04:06:40
I just found " Has anyone published a detailed comparison between different in-memory RDBMSs ?" that is related to my question. TimesTen (see also ) is a In-Memory Database from oracle. It has a lot going for it including. Fast, consistent response time High transaction throughput Standard SQL, no application rewrite Persistent and recoverable High availability and no data loss However it is priced out of the reach of most people ( $41,500.00 / Processor ). So what alternatives are there, and what are there pros and cons. (I am using .NET if it changes your answer) A popular in-memory database

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

我们两清 提交于 2019-11-29 02:53:34
问题 Closed. This question is off-topic. It is not currently accepting answers. Want to improve this question? Update the question so it's on-topic for Stack Overflow. Closed 2 years ago . 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

Why Apache Kafka Streams uses RocksDB and if how is it possible to change it?

大兔子大兔子 提交于 2019-11-29 02:20:57
问题 During investigation within new features in Apache Kafka 0.9 and 0.10, we had used KStreams and KTables. There is interesting fact, that Kafka uses RocksDB internally. See Introducing Kafka Streams: Stream Processing Made Simple. RocksDB is not written in JVN compatible language, so it needs careful handling of the deployment, as it needs extra shared library (OS dependent). And here there are simple questions: Why Apache Kafka Streams uses RocksDB? How is it possible to change it? I had