Category: NuoDB

Author: . Interested in NuoDB's elastic SQL database and want to know how it all works? Download our white paper on NuoDB's database architecture.Looking for the next-generation database As a NuoDB solution architect, I constantly talk to people about what they’re looking for in a database. More and more often, architects and CTOs tell us that they’re building their next-generation data center – often using containers or cloud infrastructure - and they need a database that fits this model. In their ideal world, they want a familiar relational database – but they want one that can deliver elastic capacity, maintain ... Read More

Author: ariff. With NuoDB v3.4, we changed how we package and version our JDBC and Hibernate drivers.Previously, we have always versioned and packaged the JDBC and Hibernate drivers with the NuoDB database. This tight coupling with the NuoDB database version has led to a lot of confusion on which driver version to use with which release. Customers assumed that the version shipped with the NuoDB database is the only version that can be used with that database version. This is not correct. In fact, it hasn’t been correct since NuoDB v1.0. We have maintained compatibility with every release. You can ... Read More

Author: . With NuoDB v3.4, we changed how we package and version our JDBC and Hibernate drivers.Previously, we have always versioned and packaged the JDBC and Hibernate drivers with the NuoDB database. This tight coupling with the NuoDB database version has led to a lot of confusion on which driver version to use with which release. Customers assumed that the version shipped with the NuoDB database is the only version that can be used with that database version. This is not correct. In fact, it hasn’t been correct since NuoDB v1.0. We have maintained compatibility with every release. You can ... Read More

Author: mkysel. As I explained in a previous blog post, sometimes MVCC is not sufficient and an operation needs to block out all other concurrent modifications. NuoDB is able to lock three types of lockable resources: tables, schemas, and sequences. A resource can either be locked in SHARED mode (which still allows record modification, but no metadata modification) or EXCLUSIVE which prevents any concurrent modification.EXCLUSIVE access is required for DDL that visits all records (various index operations for example) and distributed concurrent access is not possible. Exclusive access can also be used by operations that need to work around MVCC ... Read More

Author: . As I explained in a previous blog post, sometimes MVCC is not sufficient and an operation needs to block out all other concurrent modifications. NuoDB is able to lock three types of lockable resources: tables, schemas, and sequences. A resource can either be locked in SHARED mode (which still allows record modification, but no metadata modification) or EXCLUSIVE which prevents any concurrent modification.EXCLUSIVE access is required for DDL that visits all records (various index operations for example) and distributed concurrent access is not possible. Exclusive access can also be used by operations that need to work around MVCC ... Read More

Author: NuoDB. Try our Community Edition (CE) on Red Hat OpenShift!We are pleased to announce that with NuoDB v3.3, our leading distributed SQL database is now integrated into Red Hat OpenShift. This enables customers to fully develop, test, deploy and operate applications needing a SQL database fully within OpenShift. OpenShift is Red Hat’s open source container application platform based on the Kubernetes for enterprise application development and deployment. The NuoDB Community Edition (CE) is a full featured, free to use version of NuoDB, limited to three Transaction Engine (TE) processes, and one Storage Manager (SM). The CE is ideal for ... Read More

Author: . Try our Community Edition (CE) on Red Hat OpenShift!We are pleased to announce that with NuoDB v3.3, our leading distributed SQL database is now integrated into Red Hat OpenShift. This enables customers to fully develop, test, deploy and operate applications needing a SQL database fully within OpenShift. OpenShift is Red Hat’s open source container application platform based on the Kubernetes for enterprise application development and deployment. The NuoDB Community Edition (CE) is a full featured, free to use version of NuoDB, limited to three Transaction Engine (TE) processes, and one Storage Manager (SM). The CE is ideal for ... Read More

Author: mkysel. IntroLet us imagine a scenario that needs to prevent MVCC write skews... One transaction increases the salary of everyone in a department by 10%; another transaction inserts a new employee with a salary X. Since the two transactions do not conflict, MVCC does not prevent either of them from committing. After both resolve, the overall salary in the department could be above the budget. To prevent a similar situation, the application developer might want to have exclusive access to the table. NuoDB 3.2.2 exposes a new type of lock that guarantees exclusive access to a resource across the ... Read More

Author: . IntroLet us imagine a scenario that needs to prevent MVCC write skews... One transaction increases the salary of everyone in a department by 10%; another transaction inserts a new employee with a salary X. Since the two transactions do not conflict, MVCC does not prevent either of them from committing. After both resolve, the overall salary in the department could be above the budget. To prevent a similar situation, the application developer might want to have exclusive access to the table. NuoDB 3.2.2 exposes a new type of lock that guarantees exclusive access to a resource across the ... Read More

Author: mkysel. IntroAs a distributed, ACID-compliant database, we get a lot of questions about how NuoDB works, and how it compares to more well-known architectures. In particular, people want to understand how NuoDB compares to a master / master architecture, and (related) how we handle lock management. This post will discuss both. We will also discuss when shared-nothing architecture is viable and when conflicting decisions need to coordinated. In this blog post, we will discuss the concept of Chairmanship, NuoDB's answer to distributed coordination. We will prove that Chairmanship is both consistent and resilient to failure. But before we go ... Read More