--- layout: "language" page_title: "Backend Type: pg" sidebar_current: "docs-backends-types-standard-pg" description: |- Terraform can store state remotely in a Postgres database with locking. --- # pg **Kind: Standard (with locking)** Stores the state in a [Postgres database](https://www.postgresql.org) version 10 or newer. This backend supports [state locking](/docs/language/state/locking.html). ## Example Configuration ```hcl terraform { backend "pg" { conn_str = "postgres://user:pass@db.example.com/terraform_backend" } } ``` Before initializing the backend with `terraform init`, the database must already exist: ``` createdb terraform_backend ``` This `createdb` command is found in [Postgres client applications](https://www.postgresql.org/docs/10/reference-client.html) which are installed along with the database server. We recommend using a [partial configuration](/docs/language/settings/backends/configuration.html#partial-configuration) for the `conn_str` variable, because it typically contains access credentials that should not be committed to source control: ```hcl terraform { backend "pg" {} } ``` Then, set the credentials when initializing the configuration: ``` terraform init -backend-config="conn_str=postgres://user:pass@db.example.com/terraform_backend" ``` To use a Postgres server running on the same machine as Terraform, configure localhost with SSL disabled: ``` terraform init -backend-config="conn_str=postgres://localhost/terraform_backend?sslmode=disable" ``` ## Data Source Configuration To make use of the pg remote state in another configuration, use the [`terraform_remote_state` data source](/docs/language/state/remote-state-data.html). ```hcl data "terraform_remote_state" "network" { backend = "pg" config { conn_str = "postgres://localhost/terraform_backend" } } ``` ## Configuration Variables The following configuration options or environment variables are supported: * `conn_str` - (Required) Postgres connection string; a `postgres://` URL * `schema_name` - Name of the automatically-managed Postgres schema, default `terraform_remote_state`. * `skip_schema_creation` - If set to `true`, the Postgres schema must already exist. Terraform won't try to create the schema. Useful when the Postgres user does not have "create schema" permission on the database. * `skip_table_creation` - If set to `true`, the Postgres table must already exist. Terraform won't try to create the table. Useful when the Postgres user does not have "create table" permission on the database. * `skip_index_creation` - If set to `true`, the Postgres index must already exist. Terraform won't try to create the index. Useful when the Postgres user does not have "create index" permission on the database. ## Technical Design This backend creates one table **states** in the automatically-managed Postgres schema configured by the `schema_name` variable. The table is keyed by the [workspace](/docs/language/state/workspaces.html) name. If workspaces are not in use, the name `default` is used. Locking is supported using [Postgres advisory locks](https://www.postgresql.org/docs/9.5/explicit-locking.html#ADVISORY-LOCKS). [`force-unlock`](https://www.terraform.io/docs/cli/commands/force-unlock.html) is not supported, because these database-native locks will automatically unlock when the session is aborted or the connection fails. To see outstanding locks in a Postgres server, use the [`pg_locks` system view](https://www.postgresql.org/docs/9.5/view-pg-locks.html). The **states** table contains: * a serial integer `id`, used as the key for advisory locks * the workspace `name` key as *text* with a unique index * the Terraform state `data` as *text*