SQL Database - Bicep Patterns

⛔ CRITICAL — SQL Server Bicep MUST use Entra-only authentication. NEVER include administratorLogin or administratorLoginPassword anywhere in a Bicep file — not even inside a conditional (condition ? { ... } : { administratorLoginPassword: ... }) branch. If either property name appears anywhere in the file, the deployment will be rejected. Always use the pattern below.

Basic Setup (Entra-Only Authentication)

Required approach — Uses Microsoft Entra ID authentication only. Required for subscriptions with Entra-only policies; SQL admin authentication is disabled by policy in those environments.

param principalId string
param principalName string
@allowed(['User', 'Group', 'Application'])
param principalType string = 'User'

resource sqlServer 'Microsoft.Sql/servers@2022-05-01-preview' = {
  name: '${resourcePrefix}-sql-${uniqueHash}'
  location: location
  properties: {
    administrators: {
      administratorType: 'ActiveDirectory'
      principalType: principalType
      login: principalName
      sid: principalId
      tenantId: subscription().tenantId
      azureADOnlyAuthentication: true
    }
    minimalTlsVersion: '1.2'
  }
}

resource sqlDatabase 'Microsoft.Sql/servers/databases@2022-05-01-preview' = {
  parent: sqlServer
  name: 'appdb'
  location: location
  sku: {
    name: 'Basic'
    tier: 'Basic'
  }
  properties: {
    collation: 'SQL_Latin1_General_CP1_CI_AS'
    maxSizeBytes: 2147483648  // 2 GB
  }
}

resource sqlFirewallAzure 'Microsoft.Sql/servers/firewallRules@2022-05-01-preview' = {
  parent: sqlServer
  name: 'AllowAzureServices'
  properties: {
    startIpAddress: '0.0.0.0'
    endIpAddress: '0.0.0.0'
  }
}

Set Entra admin parameters:

1. Get current user info:

az ad signed-in-user show --query "{id:id, name:displayName}" -o json

⚠️ Warning: If deploying from CI/CD with a service principal, set principalType to 'Application'. The default 'User' only works for interactive (human) deployments. Mismatched principalType causes UnmatchedPrincipalType errors during provisioning.

1. Set as azd environment variables:

PRINCIPAL_INFO=$(az ad signed-in-user show --query "{id:id, name:displayName}" -o json)
azd env set AZURE_PRINCIPAL_ID $(echo $PRINCIPAL_INFO | jq -r '.id')
azd env set AZURE_PRINCIPAL_NAME $(echo $PRINCIPAL_INFO | jq -r '.name')

💡 Tip: Set these variables immediately after azd init to avoid deployment failures. The Bicep principalId and principalName parameters will automatically use these environment variables.

⚠️ MANDATORY: Connection String with Entra Auth Parameter

CRITICAL: When outputting SQL connection strings in Bicep (e.g., in App Service connectionStrings or as outputs), ALWAYS include an Authentication parameter. Use Authentication=Active Directory Default for general scenarios or Authentication=Active Directory Managed Identity when a user-assigned managed identity with a specific User Id is required. A bare Server=tcp:...;Database=...; connection string without this parameter will not authenticate via Entra ID and the app will fail to connect.

Correct pattern in Bicep (Active Directory Default):

connectionStrings: [
  {
    name: 'DefaultConnection'
    connectionString: 'Server=tcp:${sqlServer.properties.fullyQualifiedDomainName},1433;Database=${sqlDatabase.name};Authentication=Active Directory Default;Encrypt=True;TrustServerCertificate=False;'
    type: 'SQLAzure'
  }
]

With user-assigned managed identity:

connectionStrings: [
  {
    name: 'DefaultConnection'
    connectionString: 'Server=tcp:${sqlServer.properties.fullyQualifiedDomainName},1433;Database=${sqlDatabase.name};Authentication=Active Directory Managed Identity;User Id=${uamiClientId};Encrypt=True;TrustServerCertificate=False;'
    type: 'SQLAzure'
  }
]

❌ DO NOT generate connection strings without an Authentication=Active Directory Default or Authentication=Active Directory Managed Identity parameter. ❌ DO NOT use manual AccessToken assignment or DefaultAzureCredential().GetToken() in application code as an alternative to the connection string parameter.

Serverless Configuration

resource sqlDatabase 'Microsoft.Sql/servers/databases@2022-05-01-preview' = {
  parent: sqlServer
  name: 'appdb'
  location: location
  sku: {
    name: 'GP_S_Gen5'
    tier: 'GeneralPurpose'
    family: 'Gen5'
    capacity: 2
  }
  properties: {
    autoPauseDelay: 60  // minutes
    minCapacity: json('0.5')
  }
}

Private Endpoint

resource sqlPrivateEndpoint 'Microsoft.Network/privateEndpoints@2023-05-01' = {
  name: '${sqlServer.name}-pe'
  location: location
  properties: {
    subnet: {
      id: subnet.id
    }
    privateLinkServiceConnections: [
      {
        name: '${sqlServer.name}-connection'
        properties: {
          privateLinkServiceId: sqlServer.id
          groupIds: ['sqlServer']
        }
      }
    ]
  }
}

⛔ MANDATORY: SQL Data-Plane Access via postprovision Hook

CRITICAL: ARM/Bicep role assignments (SQL DB Contributor) only grant control-plane access. They do not grant the app data-plane access to the database. Without the T-SQL grant below, apps using Authentication=Active Directory Default will crash on startup with a login failure.

>

When you generate SQL + Managed Identity infrastructure you MUST also:

1. Add a postprovision hook to azure.yaml that runs the SQL grant script
2. Copy the pre-built scripts from scripts/grant-sql-access.sh and scripts/grant-sql-access.ps1 to scripts/ in the user's project root

azure.yaml hooks section (add or merge):

hooks:
  postprovision:
    posix:
      shell: sh
      run: ./scripts/grant-sql-access.sh
    windows:
      shell: pwsh
      run: ./scripts/grant-sql-access.ps1

Copy the pre-built scripts — Read scripts/grant-sql-access.sh and scripts/grant-sql-access.ps1 and write them verbatim to the project's scripts/ folder. Do not regenerate them from scratch.

Key behaviours of the scripts:

• Installs the rdbms-connect Azure CLI extension if not already present (required for az sql db query)
• Loads azd env get-values safely (no eval)
• Grants db_datareader + db_datawriter by default (idempotent)
• Set SQL_GRANT_DDLADMIN=true in the azd env to also grant db_ddladmin (needed for EF Core migrations)
• SERVICE_WEB_NAME takes priority over SERVICE_API_NAME when resolving the app identity

💡 Make executable: chmod +x scripts/*.sh

💡 If the app also uses EF Core migrations, combine this with the migration hook — see the azure-deploy skill's references/recipes/azd/sql-managed-identity.md.

Legacy SQL Authentication (⛔ DO NOT USE - EVER)

❌ PROHIBITED — NEVER generate administratorLogin or administratorLoginPassword properties. This applies unconditionally: do NOT include them in direct assignments, conditional expressions, ternary branches, parameter defaults, or any other construct. The text of these property names must not appear anywhere in a generated .bicep file. SQL admin authentication is disabled in all subscriptions with Entra-only policies and violates Azure security best practices. Always use the Entra-only authentication pattern at the top of this file.

>

❌ DO NOT generate conditional patterns like:

properties: useEntraAuth ? {
  administrators: {
    azureADOnlyAuthentication: true
    // ...
  }
} : {
  administratorLogin: sqlAdminLogin          // ❌ PROHIBITED
  administratorLoginPassword: sqlAdminPassword  // ❌ PROHIBITED
}

Use only the unconditional Entra-only pattern. No fallback. No toggle. No conditional.