Glossary
Access token
See Token.
Active time
The amount of active compute hours. Neon Free Tier users are provided with 100 hours of active compute hours per month. See Free Tier for more information.
Activity Monitor
A process that monitors a Neon compute instance for activity. During periods of inactivity, the Activity Monitor gracefully places the compute into an Idle state to save energy and resources. The Activity Monitor closes idle connections after 5 minutes of inactivity. When a connection is made to an idle compute, the Activity Monitor reactivates the compute.
API
See Neon API.
API Key
A unique identifier used to authenticate a user or a calling program to an API. An API key is required to authenticate to the Neon API. For more information, see Manage API keys.
Auto-suspend compute
A feature that suspends a compute endpoint after a specified period of inactivity (5 minutes, by default) to save on compute resources. This feature is also referred to as "scale to zero". When suspended, a compute endpoint is placed into an Idle state. Otherwise, the compute endpoint is in an Active state. You can monitor the state of a compute endpoint in the Branches widget on the Neon Dashboard.
Autoscaling
A feature that allows you to specify a minimum and maximum number of Compute Units (CU) for a compute endpoint. Neon scales compute resources up and down within the specified boundaries to meet workload demand.
Availability Checker
A periodic load generated by the Control Plane to determine if a compute can start and read and write data. The Availability Checker queries a system database without accessing user data.
Backpressure
A mechanism that manages the lag between the Pageserver and compute node or the Pageserver and Write-Ahead Log (WAL) service. If the WAL service runs ahead of the Pageserver, the time to serve page requests increases, which could result in increased query times or timeout errors. The backpressure mechanism manages lag using a stop-and-wait backend throttling strategy.
Branch
A copy-on-write clone of a Neon project's primary branch or previously created child branch. A branch can be created from the current or past state of the parent branch. A branch created from the current state of the parent branch includes the databases and roles that existed in the parent branch at the time of branch creation. A branch created from a past state of the parent branch includes the databases and roles that existed in the past state. The data in a branch can be modified independently from its originating data. See Branching. Connecting to a database in a branch requires connecting via the branch's compute endpoint. For more information, see Connect to a branch.
Branching
A Neon feature that allows you to create a copy-on-write clone (a "branch") of your project data. See Branch.
CI/CD
Continuous integration and continuous delivery or continuous deployment.
Compute
A service that provides virtualized computing resources (CPU, memory, and storage) for running applications. A Neon compute instance (also referred to as a compute endpoint) runs PostgreSQL. The amount of compute resources available to a Neon project is defined by tier. Neon supports free and paid tiers.
Compute endpoint
A Neon compute instance. Neon creates a single read-write compute endpoint for the project's primary branch. You can choose whether or not to create a compute endpoint when creating child branches. The compute endpoint hostname is required to connect to a Neon database from a client or application. A compute endpoint hostname can be found in the Connection Details widget on the Neon Dashboard or by selecting the branch on the Branches page in the Neon Console. A compute endpoint hostname starts with an ep- prefix, as in this example: ep-polished-water-579720.us-east-2.aws.neon.tech. A compute endpoint hostname includes an endpoint_id (ep-polished-water-579720), a region slug (us-east-2), the cloud platform (aws), and Neon domain (neon.tech). For information about connecting to Neon, see Connect from any application. For more information about compute endpoints, see Manage compute endpoints.
Connection pooling
A method of creating a pool of connections and caching those connections for reuse. Neon supports PgBouncer in transaction mode for connection pooling. For more information, see Connection pooling.
Connection string
A string containing details for connecting to a Neon database. The details include a user name (role), compute endpoint hostname, and database name; for example:
postgres://casey@ep-polished-water-579720.us-east-2.aws.neon.tech/neondbThe compute endpoint hostname includes an endpoint_id (ep-polished-water-579720), a region slug (us-east-2), the cloud platform (aws), and Neon domain (neon.tech).
Connection strings for a Neon databases can be obtained from the Connection Details widget on the Neon Dashboard. For information about connecting to Neon, see Connect from any application.
Compute size
The number of Compute Units (CU) assigned to a Neon compute endpoint. One CU is equal to 1 vCPU with 4 GBs of RAM. A Neon compute endpoint can have anywhere from .25 CUs to 7 CUs. The number of CUs determines the processing capacity of the compute endpoint.
Compute time
A billing metric that measures the amount of computing capacity used within a specified time period. See Compute time.
Console
See Neon Console.
Control Plane
The part of the Neon architecture that manages cloud storage and compute resources.
Copy-on-write
A technique used to copy data efficiently. Neon uses the copy-on-write technique to copy data when creating a branch.
Data transfer
A billing metric that measures the amount of data transferred out of Neon (egress). See Data transfer.
Database
A named collection of database objects. A Neon project has a default database named neondb which resides in the default public schema. A Neon project can contain multiple databases. Users cannot manipulate system databases, such as the postgres, template0, or template1 databases.
Database branching
See Branching.
Database fleet
A collection of database instances, typically managed as a single entity.
Dedicated resources
Resources including compute and storage dedicated to a single Neon account.
Enterprise plan
A custom volume-based paid plan offered by Neon. See Neon plans.
Free Tier
A Neon service tier for which there are no usage charges. For information about Neon’s Free Tier and associated limits, see Free Tier.
LSN
Log Sequence Number. A byte offset to a location in the WAL stream. The Neon branching feature supports creating branches with data up to a specified LSN.
Neon
A fully managed serverless PostgreSQL. Neon separates storage and compute to offer modern developer features such as branching, autoscaling, and bottomless storage. For more information, see What is Neon?.
Neon API
The Neon RESTful Application Programming Interface. Any operation performed in the Neon Console can also be performed using the Neon API.
Neon Console
A browser-based graphical interface for managing Neon projects and resources.
Neon user
The user account that registers and authenticates with Neon using a GitHub or Google account. Once authenticated, a Neon user account can create and manage projects, branches, users, databases, and other project resources.
Non-primary branch
A branch created from a primary branch or another branch in your Neon project.
Page
An 8KB unit of data, which is the smallest unit that PostgreSQL uses for storing relations and indexes on disk. In Neon, a page is also the smallest unit of data that resides on a Pageserver. For information about PostgreSQL page format, see Database Page Layout, in the PostgreSQL Documentation.
Paid plan
A paid Neon service tier. See Neon plans.
Pageserver
A Neon architecture component that reads WAL records from Safekeepers to identify modified pages. The Pageserver accumulates and indexes incoming WAL records in memory and writes them to disk in batches. Each batch is written to an immutable file that is never modified after creation. Using these files, the Pageserver can quickly reconstruct any version of a page dating back to the defined retention period. Neon retains 7-day history, by default.
The Pageserver uploads immutable files to cloud storage, which is the final, highly durable destination for data. Once a file is successfully uploaded to cloud storage, the corresponding WAL records can be removed from the Safekeepers.
Passwordless authentication
The ability to authenticate without providing a password. Neon’s Passwordless auth feature supports passwordless authentication.
Platform Partnership plan
A custom volume-based paid plan offered by Neon that includes support for resale. See Neon plans.
Point-in-time restore
Restoration of data to a state that existed at an earlier time. Neon retains a data history in the form of Write-Ahead-Log (WAL) records, which allows you to restore data to an earlier time. A point-in-time restore is performed by creating a branch using the Time or LSN option. See Create a branch for more information. Neon retains 7-day history, by default.
PostgreSQL role
A PostgreSQL role named for the registered Neon account is created with each Neon project. This user can access a Neon database from a client. Older projects may have a web-access system role, used by the SQL Editor and Neon’s Passwordless auth. The web-access role is system managed. It cannot be modified, removed, or used in other authentication scenarios.
Additional PostgreSQL roles can be created in the Neon Console. You can think of a PostgreSQL role as a "database user".
In PostgreSQL, a role with the LOGIN attribute is considered the same as a database user. For additional information, refer to Database roles and Role Attributes, in the PostgreSQL documentation.
Pro plan
A usage-based paid plan offered by Neon. See Neon plans.
Project
A collection of branches, databases, roles, and other project resources and settings. A project contains a compute with a PostgreSQL server and storage for the project data.
Project sharing
A feature that allows you to share Neon projects with other Neon users. See Share a project for more information.
Project storage
The amount of data stored in your Neon project. Also, a billing metric that measures the data and history, in GiB-hours, stored in your Neon project. See Project storage.
Proxy
A Neon component that functions as a multitenant service that accepts and handles connections from clients that use the PostgreSQL protocol.
Passwordless auth
A Neon feature that allows you to connect to a Neon project with a single psql command. See Passwordless auth.
Region
The geographic location where Neon project resource are located. Neon supports creating projects in several Amazon Web Services (AWS) regions. For information about regions supported by Neon, see Regions.
Resale
Selling the Neon service as part of another service offering. Neon's Platform Partnership plan offers resale of the Neon service as an option. See Neon plans for more information.
Primary branch
Each Neon project is created with a primary branch called main. This is your project's root branch. You can rename a primary branch, but you cannot delete it. Each branch, including the primary branch, has a dedicated compute endpoint. Connecting to a branch requires connecting to the branch's compute endpoint. For more information, see Connect to a branch.
Safekeeper
A Neon architecture component responsible for the durability of database changes. PostgreSQL streams WAL records to Safekeepers. A quorum algorithm based on Paxos ensures that when a transaction is committed, it is stored on a majority of Safekeepers and can be recovered if a node is lost. Safekeepers are deployed in different availability zones to ensure high availability and durability.
Scale-to-zero
Scale-to-zero refers to Neon's Auto-suspend compute feature, which places a compute endpoint into an Idle state when it is not being used. Neon suspends a compute after five minutes of inactivity, by default.
Serverless
A cloud-based development model that enables developing and running applications without having to manage servers.
SNI
Server Name Indication. A TLS protocol extension that allows a client or browser to indicate which hostname it wants to connect to at the beginning of a TLS handshake.
SQL Editor
A feature of the Neon Console that enables running queries on a Neon database. The SQL Editor also enables saving queries, viewing query history, and analyzing or explaining queries.
Storage
Where data is recorded and stored. Neon storage consists of Pageservers, which store hot data, and a cloud object store, such as Amazon S3, that stores cold data for cost optimization and durability.
Technical Preview
A preview period during which users can try Neon.
Token
An encrypted access token that enables you to authenticate with Neon using the Neon API. An access token is generated when creating a Neon API key. For more information, see Manage API keys.
User
See Neon user and PostgreSQL role.
WAL
See Write-Ahead Logging.
WAL slice
Write-ahead logs in a specific LSN range.
WAL stream
The stream of data written to the Write-Ahead Log (WAL) during transactional processing.
Write-Ahead Logging (WAL)
A standard mechanism that ensures the durability of your data. Neon relies on WAL to separate storage and compute, and to support features such as branching and point-in-time restore.
Written data
A billing metric that measures the amount of data changes that Neon writes from compute to storage to ensure the durability of your data. See Written data.