> ## Documentation Index > Fetch the complete documentation index at: https://docs.tensor9.com/llms.txt > Use this file to discover all available pages before exploring further. # PostgreSQL Flexible Server > PostgreSQL Flexible Server APIs with Cloud Adapter. This page describes how PostgreSQL Flexible Server maps to services in the environment where the application runs. Some profiles adapt origin API calls; others translate infrastructure or document target-native behavior. ## Supported environments | Environment | Mapping | | ------------ | ------- | | AWS | API | | Google Cloud | API | API means the profile adapts origin API behavior. Infrastructure means the profile changes provisioned resources or documents a target-native alternative without promising an origin API endpoint. Check the operation and capability tables for the behavior your application depends on. ## How the targets compare Each row compares a capability of PostgreSQL Flexible Server with its adaptation on each target. A dash means this profile does not state the capability for that target. ### Cloud Adapter | Capability | PostgreSQL Flexible Server | AWS | Google Cloud | | ------------ | -------------------------- | ---- | ------------ | | API coverage | full | high | high | ## On AWS ### RDS PostgreSQL | Operation | Area | Support | Depth | Notes | | ---------------------------------------- | ------- | ------------ | ------------ | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------ | | Microsoft Entra authentication | Connect | Out of scope | Full surface | Rejected at build time: the target server does not accept Microsoft Entra tokens. A password is not substituted for the original login. | | Databases and firewall rules | Control | Supported | Most usage | Databases are created on the server. Firewall rules become security-group rules, as described on the Virtual Network page. | | Server parameters | Control | Supported | Most usage | Settings become a parameter group, applied through the target's parameter API. | | Zone-redundant high availability | Control | Supported | Common | Zone-redundant high availability becomes an RDS Multi-AZ deployment. | | flexibleServers.create / update / delete | Control | Supported | Common | An RDS PostgreSQL instance uses mapped compute and storage capacity and a target-compatible engine version. The build identifies unsupported size or version selections. | | Extensions outside the target's list | Data | Out of scope | Most usage | Rejected at build time if an extension is outside the target's allowed list, including TimescaleDB; deployment does not continue to a failing CREATE EXTENSION. | | PostgreSQL wire protocol | Data | Supported | Common | The application continues using the PostgreSQL protocol with a managed PostgreSQL server. | An Azure flexible server becomes an RDS PostgreSQL instance. Your application keeps using the PostgreSQL protocol. Zone-redundant high availability maps to Multi-AZ, and server settings become an RDS parameter group. ### Management and database connections The adapter handles the Azure server-management calls and applies the requested target database configuration. SQL connections use the target database engine. Review both paths: accepting a server update does not make a setting active, and a running server does not establish that the application can authenticate or load its extensions. ### Data and failover Transfer the database contents separately, using compatible engine versions. Include users, grants, extensions, and scheduled jobs in the cutover. Update connection configuration and test reconnection after failover. The source backup history does not become a set of target restore points. ### Compatibility differences The build rejects Microsoft Entra authentication because RDS does not accept those tokens; it does not substitute a password. It also rejects extensions outside RDS's supported set, including TimescaleDB, before they can fail on CREATE EXTENSION. ## On Google Cloud ### Cloud SQL for PostgreSQL | Operation | Area | Support | Depth | Notes | | ---------------------------------------- | ------- | ------------ | ------------ | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | | Microsoft Entra authentication | Connect | Out of scope | Full surface | Rejected at build time: the target instance does not accept Microsoft Entra tokens. A password is not substituted for the original login. | | Databases and firewall rules | Control | Supported | Most usage | Databases are created on the instance. Firewall rules become authorized networks, as described on the Virtual Network page. | | Server parameters | Control | Supported | Most usage | Settings become database flags, applied through the target's instance API. | | Zone-redundant high availability | Control | Supported | Common | Zone-redundant high availability becomes a regional Cloud SQL instance. | | flexibleServers.create / update / delete | Control | Supported | Common | A Cloud SQL for PostgreSQL instance uses mapped compute and storage capacity and a target-compatible engine version. The build identifies unsupported size or version selections. | | Extensions outside the target's list | Data | Out of scope | Most usage | Rejected at build time if an extension is outside the target's allowed list; deployment does not continue to a failing CREATE EXTENSION. | | PostgreSQL wire protocol | Data | Supported | Common | The application continues using the PostgreSQL protocol with a managed PostgreSQL server. | A flexible server becomes a Cloud SQL for PostgreSQL instance, with zone-redundant high availability mapped to a regional instance and server settings to database flags. Your application continues to use the PostgreSQL protocol. ### Management and database connections The adapter handles the Azure server-management calls and applies the requested target database configuration. SQL connections use the target database engine. Review both paths: accepting a server update does not make a setting active, and a running server does not establish that the application can authenticate or load its extensions. ### Data and failover Transfer the database contents separately, using compatible engine versions. Include users, grants, extensions, and scheduled jobs in the cutover. Update connection configuration and test reconnection after failover. The source backup history does not become a set of target restore points. ### Compatibility differences Microsoft Entra tokens are not accepted by the target. The build rejects this authentication method and any extension outside the target's allowed list. ## Existing data and credentials Selecting a backend does not copy existing data, credentials or access policies. Plan and verify migration separately before changing an application's endpoint. Do not assume an identifier, credential or encrypted value from the origin service works unchanged on the target. ## Configure, tune and debug Start with [setup](/cloud-adapter/getting-started/overview) and [configuration](/cloud-adapter/configuration/overview). Use [tuning](/cloud-adapter/tuning/overview) to understand supported request tags, [debugging](/cloud-adapter/debugging/overview) to investigate a request, and [High Fidelity Cloud Emulators](/cloud-adapter/local-testing/overview) to validate a bounded reproduction.