Glossary of Terms¶
Not sure what a server, schema, or extension means? This glossary explains key PostGIS and pgAdmin concepts to help you navigate and manage your hosted database with confidence.
| Term | Description |
|---|---|
| 🖥️ Server | A PostgreSQL instance that hosts one or more databases. In pgAdmin, you connect to a server to browse, manage, and query your data. |
| 🗃️ Database | A collection of schemas, tables, views, and extensions. Each database stores a specific set of project or application data. |
| 📁 Schema | A logical container inside a database used to organise tables, views, and functions (e.g., public, admin, gis). |
| 📄 Table | A structured collection of rows and columns used to store data. In PostGIS, tables can contain both attribute and spatial geometry data. |
| 🧭 Geometry Column | A special column in a table that stores spatial objects such as points, lines, or polygons. |
| 🧩 Extension | Adds extra capabilities to a PostgreSQL database. PostGIS is an extension that enables spatial functionality. |
| 🌍 PostGIS | A PostgreSQL extension that adds support for spatial data types, spatial indexes, and GIS functions. |
| 📊 View | A virtual table based on the result of a SQL query. Views do not store data themselves but provide simplified or filtered access to data. |
| 🔍 Query Tool | pgAdmin’s built-in SQL editor used to run queries, create tables, update data, and manage your spatial database. |
| ⚙️ Function | A reusable block of logic written in SQL or PL/pgSQL. PostGIS provides many spatial functions such as ST_Buffer or ST_Intersection. |
| 📂 Backup | A saved copy of a database or schema that can be restored later. Essential for disaster recovery and safe deployments. |
| ♻️ Restore | The process of loading a previous backup into a PostgreSQL server, recreating schemas, tables, and data. |
| 🔐 Role | A PostgreSQL user or group with assigned permissions for accessing or modifying database objects. |
| 🛡️ Privileges | Permissions that control what a role can do—such as SELECT, INSERT, UPDATE, DELETE, or EXECUTE. |
| 🏷️ Primary Key | A unique identifier for each row in a table. Often required for syncing, editing, and spatial indexing. |
| 🧱 Index | A performance feature that speeds up searching and filtering of table data. Spatial indexes (GiST) are essential for PostGIS layers. |
| 🛰️ SRID | Spatial Reference Identifier that defines the coordinate system for geometry data (e.g., EPSG:4326, EPSG:3857). |
| 🧮 Spatial Function | Any PostGIS function used for geometry operations—buffering, clipping, measuring distances, intersecting, etc. |
| 📡 Connection | The configuration pgAdmin uses to access your hosted PostgreSQL server, including host, port, username, and SSL details. |