执行此操作的最佳方法是使用schedule Azure Automation进行日常工作。在下面，您将找到可以在Azure自动化上使用的PowerShell运行手册，以将数据库备份到Azure存储帐户。

<#
.SYNOPSIS
    This Azure Automation runbook automates Azure SQL database backup to Blob storage and deletes old backups from blob storage. 

.DESCRIPTION
    You should use this Runbook if you want manage Azure SQL database backups in Blob storage. 
    This runbook can be used together with Azure SQL Point-In-Time-Restore.

    This is a PowerShell runbook,as opposed to a PowerShell Workflow runbook.

.PARAMETER ResourceGroupName
    Specifies the name of the resource group where the Azure SQL Database server is located

.PARAMETER DatabaseServerName
    Specifies the name of the Azure SQL Database Server which script will backup

.PARAMETER DatabaseAdminUsername
    Specifies the administrator username of the Azure SQL Database Server

.PARAMETER DatabaseAdminPassword
    Specifies the administrator password of the Azure SQL Database Server

.PARAMETER DatabaseNames
    Comma separated list of databases script will backup

.PARAMETER StorageAccountName
    Specifies the name of the storage account where backup file will be uploaded

.PARAMETER BlobStorageEndpoint
    Specifies the base URL of the storage account

.PARAMETER StorageKey
    Specifies the storage key of the storage account

.PARAMETER BlobContainerName
    Specifies the container name of the storage account where backup file will be uploaded. Container will be created if it does not exist.

.PARAMETER RetentionDays
    Specifies the number of days how long backups are kept in blob storage. Script will remove all older files from container. 
    For this reason dedicated container should be only used for this script.

.INPUTS
    None.

.OUTPUTS
    Human-readable informational and error messages produced during the job. Not intended to be consumed by another runbook.

#>

param(
    [parameter(Mandatory=$true)]
    [String] $ResourceGroupName,[parameter(Mandatory=$true)]
    [String] $DatabaseServerName,[parameter(Mandatory=$true)]
    [String]$DatabaseAdminUsername,[parameter(Mandatory=$true)]
    [String]$DatabaseAdminPassword,[parameter(Mandatory=$true)]
    [String]$DatabaseNames,[parameter(Mandatory=$true)]
    [String]$StorageAccountName,[parameter(Mandatory=$true)]
    [String]$BlobStorageEndpoint,[parameter(Mandatory=$true)]
    [String]$StorageKey,[parameter(Mandatory=$true)]
    [string]$BlobContainerName,[parameter(Mandatory=$true)]
    [Int32]$RetentionDays
)

$ErrorActionPreference = 'stop'

function Login() {
    $connectionName = "AzureRunAsConnection"
    try
    {
        $servicePrincipalConnection = Get-AutomationConnection -Name $connectionName         

        Write-Verbose "Logging in to Azure..." -Verbose

        Add-AzureRmAccount `
            -ServicePrincipal `
            -TenantId $servicePrincipalConnection.TenantId `
            -ApplicationId $servicePrincipalConnection.ApplicationId `
            -CertificateThumbprint $servicePrincipalConnection.CertificateThumbprint | Out-Null
    }
    catch {
        if (!$servicePrincipalConnection)
        {
            $ErrorMessage = "Connection $connectionName not found."
            throw $ErrorMessage
        } else{
            Write-Error -Message $_.Exception
            throw $_.Exception
        }
    }
}

function Create-Blob-Container([string]$blobContainerName,$storageContext) {
    Write-Verbose "Checking if blob container '$blobContainerName' already exists" -Verbose
    if (Get-AzureStorageContainer -ErrorAction "Stop" -Context $storageContext | Where-Object { $_.Name -eq $blobContainerName }) {
        Write-Verbose "Container '$blobContainerName' already exists" -Verbose
    } else {
        New-AzureStorageContainer -ErrorAction "Stop" -Name $blobContainerName -Permission Off -Context $storageContext
        Write-Verbose "Container '$blobContainerName' created" -Verbose
    }
}

function Export-To-Blob-Storage([string]$resourceGroupName,[string]$databaseServerName,[string]$databaseAdminUsername,[string]$databaseAdminPassword,[string[]]$databaseNames,[string]$storageKey,[string]$blobStorageEndpoint,[string]$blobContainerName) {
    Write-Verbose "Starting database export to databases '$databaseNames'" -Verbose
    $securePassword = ConvertTo-SecureString –String $databaseAdminPassword –AsPlainText -Force 
    $creds = New-Object –TypeName System.Management.Automation.PSCredential –ArgumentList $databaseAdminUsername,$securePassword

    foreach ($databaseName in $databaseNames.Split(",").Trim()) {
        Write-Output "Creating request to backup database '$databaseName'"

        $bacpacFilename = $databaseName + (Get-Date).ToString("yyyyMMddHHmm") + ".bacpac"
        $bacpacUri = $blobStorageEndpoint + $blobContainerName + "/" + $bacpacFilename

        $exportRequest = New-AzureRmSqlDatabaseExport -ResourceGroupName $resourceGroupName –ServerName $databaseServerName `
            –DatabaseName $databaseName –StorageKeytype "StorageAccessKey" –storageKey $storageKey -StorageUri $BacpacUri `
            –AdministratorLogin $creds.UserName –AdministratorLoginPassword $creds.Password -ErrorAction "Stop"

        # Print status of the export
        Get-AzureRmSqlDatabaseImportExportStatus -OperationStatusLink $exportRequest.OperationStatusLink -ErrorAction "Stop"
    }
}

function Delete-Old-Backups([int]$retentionDays,[string]$blobContainerName,$storageContext) {
    Write-Output "Removing backups older than '$retentionDays' days from blob: '$blobContainerName'"
    $isOldDate = [DateTime]::UtcNow.AddDays(-$retentionDays)
    $blobs = Get-AzureStorageBlob -Container $blobContainerName -Context $storageContext
    foreach ($blob in ($blobs | Where-Object { $_.LastModified.UtcDateTime -lt $isOldDate -and $_.BlobType -eq "BlockBlob" })) {
        Write-Verbose ("Removing blob: " + $blob.Name) -Verbose
        Remove-AzureStorageBlob -Blob $blob.Name -Container $blobContainerName -Context $storageContext
    }
}

Write-Verbose "Starting database backup" -Verbose

$StorageContext = New-AzureStorageContext -StorageAccountName $storageAccountName -StorageAccountKey $storageKey

Login

Create-Blob-Container `
    -blobContainerName $blobContainerName `
    -storageContext $storageContext

Export-To-Blob-Storage `
    -resourceGroupName $ResourceGroupName `
    -databaseServerName $DatabaseServerName `
    -databaseAdminUsername $DatabaseAdminUsername `
    -databaseAdminPassword $DatabaseAdminPassword `
    -databaseNames $DatabaseNames `
    -storageKey $StorageKey `
    -blobStorageEndpoint $BlobStorageEndpoint `
    -blobContainerName $BlobContainerName

Delete-Old-Backups `
    -retentionDays $RetentionDays `
    -storageContext $StorageContext `
    -blobContainerName $BlobContainerName

Write-Verbose "Database backup script finished" -Verbose