Glossary
This glossary includes database and distributed-system terms that are often used when using ScalarDB.
ACID​
Atomicity, consistency, isolation, and durability (ACID) is a set of properties that ensure database transactions are processed reliably, maintaining integrity even in cases of errors or system failures.
concurrency control​
Concurrency control in databases ensures that multiple transactions can occur simultaneously without causing data inconsistency, usually through mechanisms like locking or timestamp ordering.
consensus​
Consensus in distributed systems refers to the process of achieving agreement among multiple computers or nodes on a single data value or system state.
data federation​
Data federation is the process of integrating data from different sources without moving the data, creating a unified view for querying and analysis.
data mesh​
A data mesh is a decentralized data architecture that enables domain teams to independently perform cross-domain analysis, addressing scalability and ownership challenges.
data virtualization​
Data virtualization is similar to data federation in many aspects, meaning that it virtualizes multiple data sources into a unified view, simplifying queries without moving the data.
database anomalies​
Database anomalies are inconsistencies or errors in data that can occur when operations such as insertions, updates, or deletions are performed without proper transaction management.
federation engine​
A federation engine facilitates data integration and querying across multiple disparate data sources, often as part of a data federation architecture.
global transaction​
A global transaction spans multiple databases or distributed systems and ensures that all involved systems commit or roll back changes as a single unit.
heterogeneous databases​
Heterogeneous databases refer to systems composed of different database technologies that may have distinct data models, query languages, and transaction mechanisms.
HTAP​
Hybrid transactional/analytical processing (HTAP) refers to a system that can handle both transactional and analytical workloads concurrently on the same data set, removing the need for separate databases.
JDBC​
Java Database Connectivity (JDBC) is an API that allows Java applications to interact with databases, providing methods for querying and updating data in relational databases.
linearizability​
Linearizability is a strong consistency model in distributed systems where operations appear to occur atomically in some order, and each operation takes effect between its start and end.
NoSQL databases​
NoSQL databases are non-relational databases designed for specific data models, such as document, key-value, wide-column, or graph stores, often used for handling large-scale, distributed data.
Paxos​
Paxos is a family of protocols used in distributed systems to achieve consensus, even in the presence of node failures.
PITR​
Point-in-time recovery (PITR) allows a database to be restored to a previous state at any specific time, usually after an unintended event like data corruption.
polystores​
Polystores are database architectures that allow users to interact with multiple, heterogeneous data stores, each optimized for a specific workload or data type, as if they were a single system.
read-committed isolation​
Read-committed isolation is an isolation level where each transaction sees only committed data, preventing dirty reads but allowing non-repeatable reads.
relational databases​
Relational databases store data in tables with rows and columns, using a structured query language (SQL) to define, query, and manipulate the data.
replication​
Replication in databases involves copying and distributing data across multiple machines or locations to ensure reliability, availability, and fault tolerance.
Saga​
The Saga pattern is a method for managing long-running transactions in a distributed system, where each operation in the transaction is followed by a compensating action in case of failure.
serializable isolation​
Serializable isolation (serializability) is the highest isolation level in transactional systems, ensuring that the outcome of concurrently executed transactions is the same as if they were executed sequentially.
snapshot isolation​
Snapshot isolation is an isolation level that allows transactions to read a consistent snapshot of the database, protecting them from seeing changes made by other transactions until they complete.
TCC​
Try-Confirm/Cancel (TCC) is a pattern for distributed transactions that splits an operation into three steps, allowing for coordination and recovery across multiple systems.
transaction​
A transaction in databases is a sequence of operations treated as a single logical unit of work, ensuring consistency and integrity, typically conforming to ACID properties.
transaction manager​
A transaction manager coordinates the execution of transactions across multiple systems or databases, ensuring that all steps of the transaction succeed or fail as a unit.
two-phase commit​
Two-phase commit is a protocol for ensuring all participants in a distributed transaction either commit or roll back the transaction, ensuring consistency across systems.