# SkillPatch skill: azure-resource-manager-postgresql-dotnet

This skill provides detailed guidance for managing Azure PostgreSQL Flexible Server deployments using the Azure.ResourceManager.PostgreSql .NET SDK. It covers authentication, resource hierarchy, and core workflows including creating servers, databases, firewall rules, configurations, and backups. It is designed for .NET developers working with Azure Database for PostgreSQL Flexible Server.

You (the agent) were given this URL and asked to use this skill. This is a **public** skill — no SkillPatch account, API key, or prior setup is required. Two ways to use it:

**1. Use it right now** — the skill's complete file tree (SKILL.md + all reference files) is inlined below; read `SKILL.md` first, then follow it, consulting the other files as it directs.

**2. Install the exact package onto disk** (recommended if you can run a shell — this reproduces the skill byte-for-byte, including any binary assets that can't be inlined):

```bash
mkdir -p .claude/skills/azure-resource-manager-postgresql-dotnet
curl -sSL https://skillpatch.dev/install_skill/azure-resource-manager-postgresql-dotnet | tar -xz -C .claude/skills/
```

(`.claude/skills/` is Claude Code's convention; use whatever directory your agent loads skills from.)


---

## Skill files (1)

- `SKILL.md`


### `SKILL.md`

````markdown
---
name: azure-resource-manager-postgresql-dotnet
description: |
  Azure PostgreSQL Flexible Server SDK for .NET. Database management for PostgreSQL Flexible Server deployments. Use for creating servers, databases, firewall rules, configurations, backups, and high availability. Triggers: "PostgreSQL", "PostgreSqlFlexibleServer", "PostgreSQL Flexible Server", "Azure Database for PostgreSQL", "PostgreSQL database management", "PostgreSQL firewall", "PostgreSQL backup", "Postgres".
license: MIT
metadata:
  author: Microsoft
  version: "1.0.0"
  package: Azure.ResourceManager.PostgreSql
---

# Azure.ResourceManager.PostgreSql (.NET)

Azure Resource Manager SDK for managing PostgreSQL Flexible Server deployments.

## Installation

```bash
dotnet add package Azure.ResourceManager.PostgreSql
dotnet add package Azure.Identity
```

**Current Version**: v1.2.0 (GA)  
**API Version**: 2023-12-01-preview

> **Note**: This skill focuses on PostgreSQL Flexible Server. Single Server is deprecated and scheduled for retirement.

## Environment Variables

```bash
AZURE_SUBSCRIPTION_ID=<your-subscription-id>  # Required: Azure subscription ID
AZURE_RESOURCE_GROUP=<your-resource-group>  # Required: resource group name
AZURE_POSTGRESQL_SERVER_NAME=<your-postgresql-server>  # Required: PostgreSQL Flexible Server name
AZURE_TOKEN_CREDENTIALS=prod  # Required only if DefaultAzureCredential is used in production
```

## Authentication

```csharp
using Azure.Identity;
using Azure.ResourceManager;
using Azure.ResourceManager.PostgreSql;
using Azure.ResourceManager.PostgreSql.FlexibleServers;

// Local dev: DefaultAzureCredential. Production: set AZURE_TOKEN_CREDENTIALS=prod or AZURE_TOKEN_CREDENTIALS=<specific_credential>
var credential = new DefaultAzureCredential(
    DefaultAzureCredential.DefaultEnvironmentVariableName
);
// Or use a specific credential directly in production:
// See https://learn.microsoft.com/dotnet/api/overview/azure/identity-readme?view=azure-dotnet#credential-classes
// var credential = new ManagedIdentityCredential();
ArmClient client = new ArmClient(credential);
```

## Resource Hierarchy

```
Subscription
└── ResourceGroup
    └── PostgreSqlFlexibleServer              # PostgreSQL Flexible Server instance
        ├── PostgreSqlFlexibleServerDatabase  # Database within the server
        ├── PostgreSqlFlexibleServerFirewallRule # IP firewall rules
        ├── PostgreSqlFlexibleServerConfiguration # Server parameters
        ├── PostgreSqlFlexibleServerBackup    # Backup information
        ├── PostgreSqlFlexibleServerActiveDirectoryAdministrator # Entra ID admin
        └── PostgreSqlFlexibleServerVirtualEndpoint # Read replica endpoints
```

## Core Workflows

### 1. Create PostgreSQL Flexible Server

```csharp
using Azure.ResourceManager.PostgreSql.FlexibleServers;
using Azure.ResourceManager.PostgreSql.FlexibleServers.Models;

ResourceGroupResource resourceGroup = await client
    .GetDefaultSubscriptionAsync()
    .Result
    .GetResourceGroupAsync("my-resource-group");

PostgreSqlFlexibleServerCollection servers = resourceGroup.GetPostgreSqlFlexibleServers();

PostgreSqlFlexibleServerData data = new PostgreSqlFlexibleServerData(AzureLocation.EastUS)
{
    Sku = new PostgreSqlFlexibleServerSku("Standard_D2ds_v4", PostgreSqlFlexibleServerSkuTier.GeneralPurpose),
    AdministratorLogin = "pgadmin",
    AdministratorLoginPassword = "YourSecurePassword123!",
    Version = PostgreSqlFlexibleServerVersion.Ver16,
    Storage = new PostgreSqlFlexibleServerStorage
    {
        StorageSizeInGB = 128,
        AutoGrow = StorageAutoGrow.Enabled,
        Tier = PostgreSqlStorageTierName.P30
    },
    Backup = new PostgreSqlFlexibleServerBackupProperties
    {
        BackupRetentionDays = 7,
        GeoRedundantBackup = PostgreSqlFlexibleServerGeoRedundantBackupEnum.Disabled
    },
    HighAvailability = new PostgreSqlFlexibleServerHighAvailability
    {
        Mode = PostgreSqlFlexibleServerHighAvailabilityMode.ZoneRedundant,
        StandbyAvailabilityZone = "2"
    },
    AvailabilityZone = "1",
    AuthConfig = new PostgreSqlFlexibleServerAuthConfig
    {
        ActiveDirectoryAuth = PostgreSqlFlexibleServerActiveDirectoryAuthEnum.Enabled,
        PasswordAuth = PostgreSqlFlexibleServerPasswordAuthEnum.Enabled
    }
};

ArmOperation<PostgreSqlFlexibleServerResource> operation = await servers
    .CreateOrUpdateAsync(WaitUntil.Completed, "my-postgresql-server", data);

PostgreSqlFlexibleServerResource server = operation.Value;
Console.WriteLine($"Server created: {server.Data.FullyQualifiedDomainName}");
```

### 2. Create Database

```csharp
PostgreSqlFlexibleServerResource server = await resourceGroup
    .GetPostgreSqlFlexibleServerAsync("my-postgresql-server");

PostgreSqlFlexibleServerDatabaseCollection databases = server.GetPostgreSqlFlexibleServerDatabases();

PostgreSqlFlexibleServerDatabaseData dbData = new PostgreSqlFlexibleServerDatabaseData
{
    Charset = "UTF8",
    Collation = "en_US.utf8"
};

ArmOperation<PostgreSqlFlexibleServerDatabaseResource> operation = await databases
    .CreateOrUpdateAsync(WaitUntil.Completed, "myappdb", dbData);

PostgreSqlFlexibleServerDatabaseResource database = operation.Value;
Console.WriteLine($"Database created: {database.Data.Name}");
```

### 3. Configure Firewall Rules

```csharp
PostgreSqlFlexibleServerFirewallRuleCollection firewallRules = server.GetPostgreSqlFlexibleServerFirewallRules();

// Allow specific IP range
PostgreSqlFlexibleServerFirewallRuleData ruleData = new PostgreSqlFlexibleServerFirewallRuleData
{
    StartIPAddress = System.Net.IPAddress.Parse("10.0.0.1"),
    EndIPAddress = System.Net.IPAddress.Parse("10.0.0.255")
};

ArmOperation<PostgreSqlFlexibleServerFirewallRuleResource> operation = await firewallRules
    .CreateOrUpdateAsync(WaitUntil.Completed, "allow-internal", ruleData);

// Allow Azure services
PostgreSqlFlexibleServerFirewallRuleData azureServicesRule = new PostgreSqlFlexibleServerFirewallRuleData
{
    StartIPAddress = System.Net.IPAddress.Parse("0.0.0.0"),
    EndIPAddress = System.Net.IPAddress.Parse("0.0.0.0")
};

await firewallRules.CreateOrUpdateAsync(WaitUntil.Completed, "AllowAllAzureServicesAndResourcesWithinAzureIps", azureServicesRule);
```

### 4. Update Server Configuration

```csharp
PostgreSqlFlexibleServerConfigurationCollection configurations = server.GetPostgreSqlFlexibleServerConfigurations();

// Get current configuration
PostgreSqlFlexibleServerConfigurationResource config = await configurations
    .GetAsync("max_connections");

// Update configuration
PostgreSqlFlexibleServerConfigurationData configData = new PostgreSqlFlexibleServerConfigurationData
{
    Value = "500",
    Source = "user-override"
};

ArmOperation<PostgreSqlFlexibleServerConfigurationResource> operation = await configurations
    .CreateOrUpdateAsync(WaitUntil.Completed, "max_connections", configData);

// Common PostgreSQL configurations to tune
string[] commonParams = { 
    "max_connections", 
    "shared_buffers", 
    "work_mem", 
    "maintenance_work_mem",
    "effective_cache_size",
    "log_min_duration_statement"
};
```

### 5. Configure Entra ID Administrator

```csharp
PostgreSqlFlexibleServerActiveDirectoryAdministratorCollection admins = 
    server.GetPostgreSqlFlexibleServerActiveDirectoryAdministrators();

PostgreSqlFlexibleServerActiveDirectoryAdministratorData adminData = 
    new PostgreSqlFlexibleServerActiveDirectoryAdministratorData
{
    PrincipalType = PostgreSqlFlexibleServerPrincipalType.User,
    PrincipalName = "aad-admin@contoso.com",
    TenantId = Guid.Parse("<tenant-id>")
};

ArmOperation<PostgreSqlFlexibleServerActiveDirectoryAdministratorResource> operation = await admins
    .CreateOrUpdateAsync(WaitUntil.Completed, "<entra-object-id>", adminData);
```

### 6. List and Manage Servers

```csharp
// List servers in resource group
await foreach (PostgreSqlFlexibleServerResource server in resourceGroup.GetPostgreSqlFlexibleServers())
{
    Console.WriteLine($"Server: {server.Data.Name}");
    Console.WriteLine($"  FQDN: {server.Data.FullyQualifiedDomainName}");
    Console.WriteLine($"  Version: {server.Data.Version}");
    Console.WriteLine($"  State: {server.Data.State}");
    Console.WriteLine($"  SKU: {server.Data.Sku.Name} ({server.Data.Sku.Tier})");
    Console.WriteLine($"  HA: {server.Data.HighAvailability?.Mode}");
}

// List databases in server
await foreach (PostgreSqlFlexibleServerDatabaseResource db in server.GetPostgreSqlFlexibleServerDatabases())
{
    Console.WriteLine($"Database: {db.Data.Name}");
}
```

### 7. Backup and Point-in-Time Restore

```csharp
// List available backups
await foreach (PostgreSqlFlexibleServerBackupResource backup in server.GetPostgreSqlFlexibleServerBackups())
{
    Console.WriteLine($"Backup: {backup.Data.Name}");
    Console.WriteLine($"  Type: {backup.Data.BackupType}");
    Console.WriteLine($"  Completed: {backup.Data.CompletedOn}");
}

// Point-in-time restore
PostgreSqlFlexibleServerData restoreData = new PostgreSqlFlexibleServerData(AzureLocation.EastUS)
{
    CreateMode = PostgreSqlFlexibleServerCreateMode.PointInTimeRestore,
    SourceServerResourceId = server.Id,
    PointInTimeUtc = DateTimeOffset.UtcNow.AddHours(-2)
};

ArmOperation<PostgreSqlFlexibleServerResource> operation = await servers
    .CreateOrUpdateAsync(WaitUntil.Completed, "my-postgresql-restored", restoreData);
```

### 8. Create Read Replica

```csharp
PostgreSqlFlexibleServerData replicaData = new PostgreSqlFlexibleServerData(AzureLocation.WestUS)
{
    CreateMode = PostgreSqlFlexibleServerCreateMode.Replica,
    SourceServerResourceId = server.Id,
    Sku = new PostgreSqlFlexibleServerSku("Standard_D2ds_v4", PostgreSqlFlexibleServerSkuTier.GeneralPurpose)
};

ArmOperation<PostgreSqlFlexibleServerResource> operation = await servers
    .CreateOrUpdateAsync(WaitUntil.Completed, "my-postgresql-replica", replicaData);
```

### 9. Stop and Start Server

```csharp
PostgreSqlFlexibleServerResource server = await resourceGroup
    .GetPostgreSqlFlexibleServerAsync("my-postgresql-server");

// Stop server (saves costs when not in use)
await server.StopAsync(WaitUntil.Completed);

// Start server
await server.StartAsync(WaitUntil.Completed);

// Restart server
await server.RestartAsync(WaitUntil.Completed, new PostgreSqlFlexibleServerRestartParameter
{
    RestartWithFailover = true,
    FailoverMode = PostgreSqlFlexibleServerFailoverMode.PlannedFailover
});
```

### 10. Update Server (Scale)

```csharp
PostgreSqlFlexibleServerResource server = await resourceGroup
    .GetPostgreSqlFlexibleServerAsync("my-postgresql-server");

PostgreSqlFlexibleServerPatch patch = new PostgreSqlFlexibleServerPatch
{
    Sku = new PostgreSqlFlexibleServerSku("Standard_D4ds_v4", PostgreSqlFlexibleServerSkuTier.GeneralPurpose),
    Storage = new PostgreSqlFlexibleServerStorage
    {
        StorageSizeInGB = 256,
        Tier = PostgreSqlStorageTierName.P40
    }
};

ArmOperation<PostgreSqlFlexibleServerResource> operation = await server
    .UpdateAsync(WaitUntil.Completed, patch);
```

### 11. Delete Server

```csharp
PostgreSqlFlexibleServerResource server = await resourceGroup
    .GetPostgreSqlFlexibleServerAsync("my-postgresql-server");

await server.DeleteAsync(WaitUntil.Completed);
```

## Key Types Reference

| Type | Purpose |
|------|---------|
| `PostgreSqlFlexibleServerResource` | Flexible Server instance |
| `PostgreSqlFlexibleServerData` | Server configuration data |
| `PostgreSqlFlexibleServerCollection` | Collection of servers |
| `PostgreSqlFlexibleServerDatabaseResource` | Database within server |
| `PostgreSqlFlexibleServerFirewallRuleResource` | IP firewall rule |
| `PostgreSqlFlexibleServerConfigurationResource` | Server parameter |
| `PostgreSqlFlexibleServerBackupResource` | Backup metadata |
| `PostgreSqlFlexibleServerActiveDirectoryAdministratorResource` | Entra ID admin |
| `PostgreSqlFlexibleServerSku` | SKU (compute tier + size) |
| `PostgreSqlFlexibleServerStorage` | Storage configuration |
| `PostgreSqlFlexibleServerHighAvailability` | HA configuration |
| `PostgreSqlFlexibleServerBackupProperties` | Backup settings |
| `PostgreSqlFlexibleServerAuthConfig` | Authentication settings |

## SKU Tiers

| Tier | Use Case | SKU Examples |
|------|----------|--------------|
| `Burstable` | Dev/test, light workloads | Standard_B1ms, Standard_B2s |
| `GeneralPurpose` | Production workloads | Standard_D2ds_v4, Standard_D4ds_v4 |
| `MemoryOptimized` | High memory requirements | Standard_E2ds_v4, Standard_E4ds_v4 |

## PostgreSQL Versions

| Version | Enum Value |
|---------|------------|
| PostgreSQL 11 | `Ver11` |
| PostgreSQL 12 | `Ver12` |
| PostgreSQL 13 | `Ver13` |
| PostgreSQL 14 | `Ver14` |
| PostgreSQL 15 | `Ver15` |
| PostgreSQL 16 | `Ver16` |

## High Availability Modes

| Mode | Description |
|------|-------------|
| `Disabled` | No HA (single server) |
| `SameZone` | HA within same availability zone |
| `ZoneRedundant` | HA across availability zones |

## Best Practices

1. **Use Flexible Server** — Single Server is deprecated
2. **Enable zone-redundant HA** — For production workloads
3. **Use DefaultAzureCredential** — Prefer over connection strings
4. **Configure Entra ID authentication** — More secure than SQL auth alone
5. **Enable both auth methods** — Entra ID + password for flexibility
6. **Set appropriate backup retention** — 7-35 days based on compliance
7. **Use private endpoints** — For secure network access
8. **Tune server parameters** — Based on workload characteristics
9. **Use read replicas** — For read-heavy workloads
10. **Stop dev/test servers** — Save costs when not in use

## Error Handling

```csharp
using Azure;

try
{
    ArmOperation<PostgreSqlFlexibleServerResource> operation = await servers
        .CreateOrUpdateAsync(WaitUntil.Completed, "my-postgresql", data);
}
catch (RequestFailedException ex) when (ex.Status == 409)
{
    Console.WriteLine("Server already exists");
}
catch (RequestFailedException ex) when (ex.Status == 400)
{
    Console.WriteLine($"Invalid configuration: {ex.Message}");
}
catch (RequestFailedException ex)
{
    Console.WriteLine($"Azure error: {ex.Status} - {ex.Message}");
}
```

## Connection String

After creating the server, connect using:

```csharp
// Npgsql connection string
string connectionString = $"Host={server.Data.FullyQualifiedDomainName};" +
    "Database=myappdb;" +
    "Username=pgadmin;" +
    "Password=YourSecurePassword123!;" +
    "SSL Mode=Require;Trust Server Certificate=true;";

// With Entra ID token (recommended)
var credential = new DefaultAzureCredential();
var token = await credential.GetTokenAsync(
    new TokenRequestContext(new[] { "https://ossrdbms-aad.database.windows.net/.default" }));

string connectionString = $"Host={server.Data.FullyQualifiedDomainName};" +
    "Database=myappdb;" +
    $"Username=aad-admin@contoso.com;" +
    $"Password={token.Token};" +
    "SSL Mode=Require;";
```

## Related SDKs

| SDK | Purpose | Install |
|-----|---------|---------|
| `Azure.ResourceManager.PostgreSql` | PostgreSQL management (this SDK) | `dotnet add package Azure.ResourceManager.PostgreSql` |
| `Azure.ResourceManager.MySql` | MySQL management | `dotnet add package Azure.ResourceManager.MySql` |
| `Npgsql` | PostgreSQL data access | `dotnet add package Npgsql` |
| `Npgsql.EntityFrameworkCore.PostgreSQL` | EF Core provider | `dotnet add package Npgsql.EntityFrameworkCore.PostgreSQL` |

## Reference Links

| Resource | URL |
|----------|-----|
| NuGet Package | https://www.nuget.org/packages/Azure.ResourceManager.PostgreSql |
| API Reference | https://learn.microsoft.com/dotnet/api/azure.resourcemanager.postgresql |
| Product Documentation | https://learn.microsoft.com/azure/postgresql/flexible-server/ |
| GitHub Source | https://github.com/Azure/azure-sdk-for-net/tree/main/sdk/postgresql/Azure.ResourceManager.PostgreSql |

````