ARM templates and corresponding PowerShell script files to manage moving databases into and out of a SQL Database elastic pool.

CreateOrUpdateElasticPoolAndPopulate.json

{
  "$schema": "http://schema.management.azure.com/schemas/2014-04-01-preview/deploymentTemplate.json#",
  "contentVersion": "1.0.0.0",
  "parameters": {
    "serverName": {
      "type": "string"
    },
    "serverLocation": {
      "type": "string"
    },
    "elasticPoolName": {
      "type": "string"
    },
    "edition": {
      "type": "string",
      "defaultValue": "Standard"
    },
    "requestedServiceObjectiveId": {
      "type": "string",
      "defaultValue": "d1737d22-a8ea-4de7-9bd0-33395d2a7419"
    },
    "poolDtu": {
      "type": "int"
    },
    "databaseDtuMin": {
        "type": "int",
        "defaultValue": 0
    },
    "databaseDtuMax": {
      "type": "int"
    },
    "storageMB": {
      "type": "int",
      "defaultValue": 0
    },
    "databasesCount": {
      "type": "int"
    },
    "databases": {
      "type": "array"
    }
  },
  "variables": {},
  "resources": [
    {
      "name": "[concat(parameters('serverName'), '/', parameters('elasticPoolName'))]",
      "location": "[parameters('serverLocation')]",
      "type": "Microsoft.Sql/servers/elasticpools",
      "apiVersion": "2014-04-01-preview",
      "properties": {
        "edition": "[parameters('edition')]",
        "dtu": "[parameters('poolDtu')]",
        "databaseDtuMin": "[parameters('databaseDtuMin')]",
        "databaseDtuMax": "[parameters('databaseDtuMax')]"
      }
    },
    {
      "dependsOn": [
        "[concat('Microsoft.Sql/servers/', parameters('serverName') ,'/elasticpools/', parameters('elasticPoolName'))]"
      ],
      "name": "[concat(parameters('serverName'), '/', parameters('databases')[copyIndex()])]",
      "location": "[parameters('serverLocation')]",
      "type": "Microsoft.Sql/servers/databases",
      "apiVersion": "2014-04-01-preview",
      "properties": {
        "requestedServiceObjectiveId": "[parameters('requestedServiceObjectiveId')]",
        "elasticPoolName": "[parameters('elasticPoolName')]"
      },
      "copy": {
        "name": "addExistingDatabasesToElasticPool",
        "count": "[parameters('databasesCount')]"
      }
    }
  ]
}

CreateOrUpdatePoolAndPopulate.ps1

# ---------------------------------------------------------------------------------- 
# 
# Copyright Microsoft Corporation 
# Licensed under the Apache License, Version 2.0 (the "License"); 
# you may not use this file except in compliance with the License. 
# You may obtain a copy of the License at 
# http://www.apache.org/licenses/LICENSE-2.0 
# Unless required by applicable law or agreed to in writing, software 
# distributed under the License is distributed on an "AS IS" BASIS, 
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 
# See the License for the specific language governing permissions and 
# limitations under the License. 
# ---------------------------------------------------------------------------------- 

# PowerShell script for creating/updating an elastic pool and populating it with all databases on a server.  Does nothing 
# if there are no databases on the server.
# Requires the ARM template, CreateOrUpdateElasticPoolAndPopulate.json 

$resourceGroupName = 'MyResourceGroupName'               # existing resource group name
$serverName = 'MyServerName'                             # existing server name
$serverLocation = 'MyServerLocation'                     # existing server location, e.g. West US
$elasticPoolName = 'MyPoolName'                          # name of pool to be created
$templateFile = 'TemplateFileLocation'                   # e.g. C:\Downloads\ArmTemplates\CreateElasticPoolAndPopulate.json

$databases = get-AzureRMSqlDatabase -ServerName $serverName -ResourceGroupName $resourceGroupName | Where DatabaseName -ne 'master'
$databaseNames = $databases | % { $_.DatabaseName }

if($databaseNames.Count -gt 0) {
    New-AzureRmResourceGroupDeployment -TemplateFile $templateFile `
      -ResourceGroupName $resourceGroupName -serverName $serverName -serverLocation $serverLocation `
      -elasticPoolName $elasticPoolName -poolDtu 100 -databaseDtuMax 100 -databaseDtuMin 0 -edition Standard `
      -databases $databaseNames -databasesCount $databases.Count
}

EvacuatePool.json

{
    "$schema": "http://schema.management.azure.com/schemas/2014-04-01-preview/deploymentTemplate.json#",
    "contentVersion": "1.0.0.0",
    "parameters": {
        "serverName": {
            "type": "string"
        },
        "serverLocation": {
            "type": "string"
        },
        "elasticPoolName": {
            "type": "string"
        },
        "databasesCount": {
            "type": "int"
        },
        "databases": {
            "type": "array"
        },
        "requestedServiceObjectiveName": {
            "type": "string"
        }
    },
    "variables": {},
    "resources": [
        {
            "name": "[concat(parameters('serverName'), '/', parameters('databases')[copyIndex()])]",
            "location": "[parameters('serverLocation')]",
            "type": "Microsoft.Sql/servers/databases",
            "apiVersion": "2014-04-01-preview",
            "properties": {
                "requestedServiceObjectiveName": "[parameters('requestedServiceObjectiveName')]"
            },
            "copy": {
                "name": "removeDatabasesFromElasticPool",
                "count": "[parameters('databasesCount')]"
            }
        }
    ]
}

EvacuatePool.ps1

# ---------------------------------------------------------------------------------- 
# 
# Copyright Microsoft Corporation 
# Licensed under the Apache License, Version 2.0 (the "License"); 
# you may not use this file except in compliance with the License. 
# You may obtain a copy of the License at 
# http://www.apache.org/licenses/LICENSE-2.0 
# Unless required by applicable law or agreed to in writing, software 
# distributed under the License is distributed on an "AS IS" BASIS, 
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 
# See the License for the specific language governing permissions and 
# limitations under the License. 
# ---------------------------------------------------------------------------------- 

# PowerShell script for evacuating an elastic pool making all databases standalone with a specified service objective.
# Requires the ARM template, EvacuatePool.json

$resourceGroupName = 'MyResourceGroupName'               # existing resource group name
$serverName = 'MyServerName'                             # existing server name
$serverLocation = 'MyServerLocation'                     # existing server location, e.g. West US
$elasticPoolName = 'MyPoolName'                          # name of existing pool
$requestedServiceObjectiveName = 'ServiceObjectiveName'  # name of service objective for all dbs {Basic|S0|S1|S2|S3|P1|P2|... etc}
$templateFile = 'TemplateFileLocation'                   # e.g. C:\Downloads\ArmTemplates\EvacuatePool.json

$databases = get-AzureRMSqlElasticPoolDatabase -ServerName $serverName -ResourceGroupName $resourceGroupName -ElasticPoolName $elasticPoolName
$databaseNames = $databases | % { $_.DatabaseName }

if($databaseNames.Count -gt 0) {
    New-AzureRmResourceGroupDeployment -TemplateFile $templateFile `
      -ResourceGroupName $resourceGroupName -serverName $serverName -serverLocation $serverLocation -elasticPoolName $elasticPoolName `
      -databases $databaseNames -databasesCount $databaseNames.Count -requestedServiceObjectiveName $requestedServiceObjectiveName
}

MoveDatabasesBetweenPools.ps1

# ------------------------------------------------------------------------- 
# 
# Copyright Microsoft Corporation 
# Licensed under the Apache License, Version 2.0 (the "License"); 
# you may not use this file except in compliance with the License. 
# You may obtain a copy of the License at 
# http://www.apache.org/licenses/LICENSE-2.0 
# Unless required by applicable law or agreed to in writing, software 
# distributed under the License is distributed on an "AS IS" BASIS, 
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 
# See the License for the specific language governing permissions and 
# limitations under the License. 
# ---------------------------------------------------------------------------------- 

# PowerShell script for moving all databases from a source pool to a target pool on the same server.
# Requires the ARM template, PopulatePool.json
      
$resourceGroupName = 'MyResourceGroupName'               # existing resource group name
$serverName = 'MyServerName'                             # existing server name
$serverLocation = 'MyServerLocation'                     # existing server location, e.g. West US
$sourceElasticPoolName = 'MySourcePoolName'              # name of pool from which databases will be moved
$targetElasticPoolName = 'MyTargetPoolName'              # of pool into which databases will be moved
$templateFile = 'TemplateFileLocation'                   # e.g. C:\Downloads\ArmTemplates\PopulatePool.json

$databases = get-AzureRMSqlElasticPoolDatabase -ServerName $serverName -ResourceGroupName $resourceGroupName -ElasticPoolName $sourceElasticPoolName
$databaseNames = $databases | % { $_.DatabaseName }

if($databaseNames.Count -gt 0) {
    New-AzureRmResourceGroupDeployment -TemplateFile $templateFile `
      -ResourceGroupName $resourceGroupName -serverName $serverName -serverLocation $serverLocation -elasticPoolName $targetElasticPoolName `
      -databases $databaseNames -databasesCount $databaseNames.Count
}

PopulatePool.json

{
    "$schema": "http://schema.management.azure.com/schemas/2014-04-01-preview/deploymentTemplate.json#",
    "contentVersion": "1.0.0.0",
    "parameters": {
        "serverName": {
            "type": "string"
        },
        "serverLocation": {
            "type": "string"
        },
        "elasticPoolName": {
            "type": "string"
        },
        "requestedServiceObjectiveId": {
            "type": "string",
            "defaultValue": "d1737d22-a8ea-4de7-9bd0-33395d2a7419"
        },
        "databasesCount": {
            "type": "int"
        },
        "databases": {
            "type": "array"
        }
    },
    "variables": {},
    "resources": [
        {
            "name": "[concat(parameters('serverName'), '/', parameters('databases')[copyIndex()])]",
            "location": "[parameters('serverLocation')]",
            "type": "Microsoft.Sql/servers/databases",
            "apiVersion": "2014-04-01-preview",
            "properties": {
                "requestedServiceObjectiveId": "[parameters('requestedServiceObjectiveId')]",
                "elasticPoolName": "[parameters('elasticPoolName')]"
            },
            "copy": {
                "name": "addExistingDatabasesToElasticPool",
                "count": "[parameters('databasesCount')]"
            }
        }
    ]
}

PopulatePool.ps1

# ---------------------------------------------------------------------------------- 
# 
# Copyright Microsoft Corporation 
# Licensed under the Apache License, Version 2.0 (the "License"); 
# you may not use this file except in compliance with the License. 
# You may obtain a copy of the License at 
# http://www.apache.org/licenses/LICENSE-2.0 
# Unless required by applicable law or agreed to in writing, software 
# distributed under the License is distributed on an "AS IS" BASIS, 
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 
# See the License for the specific language governing permissions and 
# limitations under the License. 
# ---------------------------------------------------------------------------------- 

# PowerShell script for populating an elastic pool with all databases on a server.
# Requires the ARM template, PopulatePool.json 

$resourceGroupName = 'MyResourceGroupName'               # existing resource group name
$serverName = 'MyServerName'                             # existing server name
$serverLocation = 'MyServerLocation'                     # existing server location, e.g. West US
$elasticPoolName = 'MyPoolName'                          # name of existing pool
$templateFile = 'TemplateFileLocation'                   # e.g. C:\Downloads\ArmTemplates\PopulatePool.json

$databases = get-AzureRMSqlDatabase -ServerName $serverName -ResourceGroupName $resourceGroupName | Where DatabaseName -ne 'master'
$databaseNames = $databases | % { $_.DatabaseName }

if($databaseNames.Count -gt 0) {
    New-AzureRmResourceGroupDeployment -TemplateFile $templateFile `
      -ResourceGroupName $resourceGroupName -serverName $serverName -serverLocation $serverLocation -elasticPoolName $elasticPoolName `
      -databases $databaseNames -databasesCount $databaseNames.Count
}