Glossary

Glossary

Aggregate

The task of collecting a set of values to return a single value. When data is aggregated, data rows are replaced with totals or summary statistics.

Aggregator node

A node that routes queries to the leaf nodes, aggregates intermediate results, and sends the results back to a client. There are two types of aggregators: master and child.

Child aggregator (CA)

A node that can be promoted to the role of Master Aggregator in the event that the existing Master Aggregator’s host fails. Depending on the query volume, a cluster may contain zero or more child aggregators.

Cluster

A collection of SingleStoreDB aggregator and leaf nodes.

Code generation (codegen)

An industrial compiler to produce highly efficient machine code that enables low-level optimizations, which are not possible when executing queries via interpretation alone. By default, queries are interpreted first and then asynchronously compiled in the background for use in later executions. This speeds up query execution time for long and complex queries, while at the same time providing efficient query plans for later use.

Database user

A user that resides in the workspace. A database user’s lifetime is bound to that workspace such that, when a workspace is terminated, all of the users, permissions, and groups are permanently removed as well. Database users can connect to a workspace via SQL client and run SQL queries against their data. Unlike organization users, database users must be managed via SQL statements.

Deadlock

A situation when two or more transactions mutually hold and request a table write that the other transaction needs.

Hadoop Distributed File System (HDFS)

A distributed file system by Apache Hadoop. It is highly fault tolerant and designed to run on COTS (Commercial Off the Shelf) or low cost out-of-the-box hardware.

Hash index

A data structure optimized for fast equality lookups by a key.

Host

A hardware or virtual machine which holds the aggregator and leaf nodes that comprise a SingleStoreDB cluster.

information schema (info schema)

Holds the information or metadata for all the databases in a cluster.

Javascript Object Notation (JSON)

An open standard file format and data interchange format that uses human-readable text to store and transmit data objects consisting of attribute–value pairs and arrays.

JSON Web Key Sets (JWKS)

A set of keys containing public keys that can be used to authenticate any JWT.

JSON Web Token (JWT)

An open, industry standard typically used for authorization and information exchange.

Leaf node

A node that stores a subset of a cluster’s data. A leaf node functions as a storage and compute node. To optimize performance, SingleStoreDB automatically distributes data across leaf nodes into partitions. Each leaf node contains several partitions.

Master aggregator (MA)

A specialized node that’s responsible for cluster monitoring and failover. It orchestrates basic cluster operations and all DDL operations.

Metadata

Information about a database's schema, access to the database, storage, built-in programs, and or other information about the data such as date created, file size, and etc.

Node

A SingleStoreDB server. A host may contain one or more SingleStoreDB server instances.

Non-uniform memory access (NUMA)

A computer memory design used in multiprocessing. Through NUMA, a processor can access memory that’s considered “local memory” faster than it can access memory that is local to another processor, or memory that is shared between processors.

Normalized

Organizing data to appear similar across all records and fields.

Object store

A data storage architecture that manages data as objects, as opposed to other storage architectures like file systems which manages data as a file hierarchy, and block storage which manages data as blocks within sectors and tracks.

Online Analytical Processing (OLAP)

A data processing type that is designed to analyze data dimensions concurrently.

Online Transaction Processing (OLTP)

A data processing type that executes a number of transactions occurring concurrently.

Organization

Allows shared access to workspaces and related resources within a company or group.

Organization user

An organization user resides within the “control plane” of SingleStoreDB Cloud and can perform those actions that are available on the portal, such as manage organization users, manage clusters, and run SQL queries against cluster data via the portal SQL editor.

Partition

A partition contains a subset (a shard) of a database’s data. Each partition holds a vertical slice of data, distributed as per a hashing algorithm on the primary key or randomly for keyless sharded databases.

Pipelines

A feature that continuously loads data as it arrives from external sources. As a built-in component of the database, Pipelines can extract, shape (modify), and load external data without the need for third-party tools or middleware.

Portal

An application that allows you to design, manage, and monitor your SingleStore instances.

Portal user

A user that can log into the portal and access portal services. Each portal user is associated with a default organization and automatically has access to all of the workspaces and related resources within it.

Query shape

Patterns or structures in query. Some query shapes are unsupported in SingleStore.

Random-access memory (RAM)

A computer's short-term memory. It is where the data that the processor is currently using is stored temporarily. RAM can be accessed much faster than data on a hard disk, solid-state disk, or another long-term storage device, which is why RAM capacity is so important for system performance.

Replication

Ensures redundancy in a cluster. There are two types of replication: high availability - replicating partitions between the leaf nodes and cluster replication - replicating partitions between clusters.

Shard

A subset of a databases's data.

Sharding

A type of database partitioning that divides a database into smaller more easily manageable parts.

Single sign-on (SSO)

Single sign-on, where one can log into SingleStoreDB Cloud via Azure AD, Okata, and PingOne.Configure SingleStore SSO using Azure ADConfigure SingleStore SSO using OktaConfigure SingleStore SSO using PingOne

Skiplist index (Skiplist)

A data structure optimized for ordered data that allows for queries to quickly seek data by binary searching.

SQL Surface Area

The amount of components installed and or configuration options that are enabled.

Workspace

SingleStoreDB Cloud’s version of a cluster.