Questions tagged [voltdb]

VoltDB is an in-memory database designed by several well-known database system researchers, including Michael Stonebraker. It is an ACID-compliant RDBMS which uses a shared nothing architecture. It includes both enterprise and community editions. VoltDB implements the design of the academic H-Store project.

VoltDB is a NewSQL relational database that supports SQL access from within pre-compiled Java stored procedures. The unit of transaction is the stored procedure, which is Java interspersed with SQL. VoltDB relies on horizontal partitioning down to the individual hardware thread to scale, k-safety (synchronous replication) to provide high availability, and a combination of continuous snapshots and command logging for durability (crash recovery).

VoltDB is designed to take full advantage of the modern computing environment:

  • VoltDB uses in-memory storage to maximize throughput, avoiding costly disk access.
  • Further performance gains are achieved by serializing all data access, avoiding many of the time- consuming functions of traditional databases such as locking, latching, and maintaining transaction logs.
  • Scalability, reliability, and high availability are achieved through clustering and replication across multiple servers and server farms.
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Why do SQL databases use a write-ahead log over a command log?

I read about Voltdb's command log. The command log records the transaction invocations instead of each row change as in a write-ahead log. By recording only the invocation, the command logs are kept to a bare minimum, limiting the impact the disk…
user782220
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what is zookeeper port and its usage?

I am quite new for zookeeper port through which I am coming across from past few days. I introduced with zookeeper port keyword at two occasion: while configuring neo4j db cluster (link) and while running compiled voltdb catalog (link) (See Network…
agpt
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Difference between In-Memory cache and In-Memory Database

I was wondering if I could get an explanation between the differences between In-Memory cache(redis, memcached), In-Memory data grids (gemfire) and In-Memory database (VoltDB). I'm having a hard time distinguishing the key characteristics between…
Yolo49
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Successful VoltDB implementations

I've been working on a project for over half a year now, building healthcare software from the ground up. When I joined up, MySQL had been chosen as the primary data store. A few months and many headaches later, we've begun to investigate…
jthurau
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Connection Pooling in VoltDB

If I use JDBC approach, I am able to achieve connection pooling using third party library(Apache Dbcp). I am using Client based Approach, VoltDB is not exposing connection object, How to implement connection pooling? Is there any mechanism for…
c.sankhala
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Using PHP + VoltDB together?

Is there any way to use voltDB in a PHP application? It definitely seems like it have a few advantages over other Databases out there!
Industrial
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VoltDB: How to start or compile the database programmatically?

I am wondering if VoltDB can be started and controlled using plain java. Since the voltdb is provided as Java implementation it should be possible to control and start / stop a single database / server instance from within a java program. At least…
Martin Kersten
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How does VoltDB Community Edition support disk level persistence?

VoltDB's web site shows that the community edition supports full ACID (which includes the D for durability) but it doesn't look like it supports the crash recovery which seems related to the command logging. Is there a different in the 'D' part of…
Brennan Cheung
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Searching for VoltDB ODBC Driver

can someone tell me if there is a VoltDB ODBC Driver and where I can find it? I were not able to find one. I need ODBC Driver for a benchmarking tool. The tool should compare different NewSQL Databases. Kind regards Sedros
Sedros
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SQLException: Cannot submit statement in current context

I encountered this exception when calling a stored procedure through a prepared statement, however, it works for callable statement. I am wondering if it is a must to use callable statement for invoking a stored procedure in voltdb? String sql =…
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JVM Garbage collection and In Memory Java Databases

We are evaluating some Java based In Memory databases like Hazelcast and VoltDB. In case we replicate the data across multiple servers, how possible is that GC for both nodes will hit the servers at same time? For example we have two nodes with 500…
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Does VoltDB support unique indexes?

Our schema has a USER table... USER( userId, firstname, lastname, email) and we want to ensure all user's have unique email addresses. Is it possible to create a unique index in VoltDB to enforce this constraint?
raffian
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Update necessary fields only in VoltDB

I have a table with some 50 column count. Every time there is change in row I do not have a knowledge that which columns will change. I don't want to deal with each and every permutation and combination when updating the table. So when I have to do…
Kartik73
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I have a question about VoltDB.(foreign key constraint)

I am studying VoltDB. Why is there no foreign key constraint in VoltDB?? Is there a technical reason ??
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Is there a jooq dialect for VoltDB

Is there a dialect for voltdb? This will definitely help in producing dynamic sql for testing perposes.
Luke101
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