> For the complete documentation index, see [llms.txt](https://v2.dataos.info/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://v2.dataos.info/concepts/resources/vulcan/configurations/engines/postgres.md). # Postgres PostgreSQL is an open-source relational database that works with Vulcan. Use it for smaller projects, development environments, or when you want full control over your database infrastructure. ## Local or built-in scheduler **Engine adapter type**: `postgres` ### Prerequisites 1. A PostgreSQL server instance (version 12 or higher recommended) 2. A database user with appropriate permissions 3. Network connectivity to the PostgreSQL server ### Permissions Vulcan requires the following PostgreSQL permissions: * `CREATE` on the target database for creating schemas * `CREATE` on schemas for creating tables and views * `SELECT`, `INSERT`, `UPDATE`, `DELETE` on tables * `USAGE` on schemas ### Connection options All the connection parameters you can use when setting up a PostgreSQL gateway: | Option | Description | Type | Required | | ------------------ | ------------------------------------------------------------------------------- | :----: | :------: | | `type` | Engine type name. Must be `postgres` | string | Y | | `host` | The hostname of the Postgres server | string | Y | | `user` | The username to use for authentication with the Postgres server | string | Y | | `password` | The password to use for authentication with the Postgres server | string | Y | | `port` | The port number of the Postgres server | int | Y | | `database` | The name of the database instance to connect to | string | Y | | `keepalives_idle` | The number of seconds between each keepalive packet sent to the server. | int | N | | `connect_timeout` | The number of seconds to wait for the connection to the server. (Default: `10`) | int | N | | `role` | The role to use for authentication with the Postgres server | string | N | | `sslmode` | The security of the connection to the Postgres server | string | N | | `application_name` | The name of the application to use for the connection | string | N | ### Authentication methods * Username/password authentication (required). * SSL mode configuration (optional): use `sslmode: require` for secure connections in production environments. ### Docker images The following Docker images are available for running Vulcan with PostgreSQL: | Image | Description | | ----------------------------------- | -------------------------------------- | | `tmdcio/vulcan-postgres:0.228.1.19` | Main Vulcan API service for PostgreSQL | Pull the images: ```bash docker pull tmdcio/vulcan-postgres:0.228.1.19 ``` ### Materialization strategy PostgreSQL uses the following materialization strategies depending on the model kind: | Model kind | Strategy | Description | | --------------------------- | --------------------------------------- | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | | `INCREMENTAL_BY_TIME_RANGE` | DELETE by time range, then INSERT | Vulcan first deletes existing records within the target time range, then inserts the new data. This ensures data consistency and prevents duplicates when reprocessing time intervals. | | `INCREMENTAL_BY_UNIQUE_KEY` | MERGE ON unique key | Vulcan uses PostgreSQL's MERGE (UPSERT) functionality to update existing records based on the unique key or insert new ones if they do not exist. | | `INCREMENTAL_BY_PARTITION` | DELETE by partitioning key, then INSERT | Vulcan deletes existing records matching the partitioning key, then inserts the new data. This ensures partition-level consistency when reprocessing data. | | `FULL` | DROP TABLE, CREATE TABLE, INSERT | Vulcan drops the existing table, creates a new one, and inserts all data. This rebuilds the table from scratch each time. | **Learn more about materialization strategies:** * [INCREMENTAL\_BY\_TIME\_RANGE](/concepts/resources/vulcan/components/model/model_kinds.md#materialization-strategy) * [INCREMENTAL\_BY\_UNIQUE\_KEY](/concepts/resources/vulcan/components/model/model_kinds.md#materialization-strategy_1) * [INCREMENTAL\_BY\_PARTITION](/concepts/resources/vulcan/components/model/model_kinds.md#materialization-strategy_3) * [FULL](/concepts/resources/vulcan/components/model/model_kinds.md#materialization-strategy_2) {% hint style="info" %} Use `sslmode: require` for secure connections in production environments. {% endhint %} {% hint style="warning" %} Always use environment variables for passwords: `password: {{ env_var('POSTGRES_PASSWORD') }}` {% endhint %} --- # Agent Instructions This documentation is published with GitBook. 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