Transcript Migrating to Azure SQL Database Tips, Tricks and Lessons Learned

Migrating to Azure
SQL Database
Tips, Tricks and
Lessons Learned
Randolph West, Born SQL
Calgary PASS Chapter, 17 August 2016
Email: [email protected]
Twitter: @rabryst
What’s the Difference?
 Azure
SQL Database
cloud,
 SQL
cloud, cloud, shiny, shiny, shiny
Server
on-prem,
 Microsoft
earthed, traditional, legacy
is Cloud First
Azure SQL Database vs SQL Server VM

Platform-as-a-Service (PaaS)

Mostly compatible with SQL Server 2014 and 2016

Pay-as-you-go

Scale-up or scale-out instantly*

Automatically configured, patched, and upgraded

Automated backups, Point-In-Time Restore, Geo-Restore, and
Active Geo-Replication

Pay per hour, per service tier and performance level

Pay for data transfer

Total cost of application = Highly minimized administration costs +
software development costs + SQL Database service costs
Azure SQL Database vs SQL Server VM

Infrastructure-as-a-Service (IaaS)

SQL Server 2014 or 2016, installed on a virtual machine

Per-minute licencing cost (Web, Standard, Enterprise)

Or bring your own existing licence and only pay for Windows VM

Fully customisable

You are responsible for managing it (patching, maintenance,
backups)

Pay for premium storage (SSD drives: P10, P20, P30)

Total cost of application = Minimized software
development/modification costs + administration costs + SQL
Server and Windows Server licensing costs + Azure Storage costs
Which One Do I Choose?
 Do
you have to choose?
 Why?
 Are
 Is
you sure?
your company going to benefit from this?
 Are
you sure?
Azure SQL Database Limitations

https://azure.microsoft.com/en-us/documentation/articles/sqldatabase-general-limitations/

Highlights:

No Windows Authentication (Azure AD is supported)

TCP/IP on port 1433 only

No SQL Server Agent jobs (on-premises only)

Fixed Collation (default SQL_Latin1_General_CP1_CI_AS)

Restricted usernames (admin, administrator, guest, root, sa, ‘\’)
Transact-SQL Differences in Azure SQL
Database

https://azure.microsoft.com/en-us/documentation/articles/sqldatabase-transact-sql-information/

“Azure SQL Database is designed to isolate features from
any dependency on the master database. As a
consequence many server-level activities are
inappropriate for SQL Database and are unsupported.” –
Microsoft
Features Not Supported


Connection related: Endpoint statements,
ORIGINAL_DB_NAME. Windows authentication is
not available for logins or contained database
users.

Features that rely upon the SQL Server Agent or 
the MSDB database: jobs, alerts, operators,
Policy-Based Management, database mail, central 
management servers.
Cross database queries using three or four part
names. (Read-only cross-database queries are
supported by using elastic database query.)

FILESTREAM

Functions: fn_get_sql, fn_virtualfilestats,
fn_virtualservernodes
SET REMOTE_PROC_TRANSACTIONS

SHUTDOWN

sp_addmessagesp_configure options and
RECONFIGURE

sp_helpuser

Global temporary tables

Data Collector


Database Diagrams
Hardware related server settings: memory, worker
threads, CPU affinity, trace flags, etc. Use service 
levels instead.

Database Mail

HAS_DBACCESS

DATABASEPROPERTY (use DATABASEPROPERTYEX 
instead)

EXECUTE AS logins

Encryption: extensible key management

Eventing: events, event notifications, query
notifications



Service broker

Cross database ownership chaining,
TRUSTWORTHY setting

Serverless express: localdb, user instances
sp_migrate_user_to_contained

SQL Server audit (use SQL Database auditing
instead)
KILL STATS JOB

SQL Server Profiler
Linked servers, OPENQUERY, OPENROWSET,
OPENDATASOURCE, BULK INSERT, 3 and 4 part
names

SQL Server trace

Trace flags

Master/target servers

Transact-SQL debugging

.NET Framework CLR integration with SQL Server 
Triggers: Server-scoped or logon triggers
Features related to database file placement, size, 
and database files which are automatically
managed by Microsoft Azure.

Resource governor
USE statement: To change the database context
to a different database you must make a new
connection to the new database.
Features that relate to high availability which is
managed through your Microsoft Azure account:
backup, restore, AlwaysOn, database mirroring,
log shipping, recovery modes.

Server credentials

Sever-level items: Server roles,
IS_SRVROLEMEMBER, sys.login_token. Server level
permissions are not available though some are
replaced by database-level permissions. Some
server-level DMV's are not available though some
are replaced by database-level DMVs.
Features that rely upon the log reader running on
SQL Database: Push Replication, Change Data
Capture.

Semantic search

Migrating a SQL Server Database to
Azure SQL Database

https://azure.microsoft.com/en-us/documentation/articles/sqldatabase-cloud-migrate/

SQL Server Data Tools for Visual Studio (SSDT):


“SSDT uses the most recent compatibility rules to detect SQL
Database V12 incompatibilities. If incompatibilities are detected,
you can fix detected issues directly in this tool. This is currently
the recommended method to test and fix SQL Database V12
compatibility issues.” – Microsoft
Other tools can also help, but are not recommended:

SqlPackage, Export Data Tier application wizard (SSMS), SQL Server
2016 Upgrade Advisor, SQL Azure Migration Wizard (SAMW)
Migrating a SQL Server Database to
Azure SQL Database

SSMS Migration Wizard

BACPAC / BCP

BACPAC: JSON format containing database schema and data

BCP: parallel insert
Resource Limits
Source: Microsoft
Understanding DTUs

Database Transaction Unit (DTU):


Azure SQL Database benchmark overview:


Combination of I/O, RAM, CPU and log writes in some magical*
formula
https://azure.microsoft.com/en-us/documentation/articles/sqldatabase-benchmark-overview/
DTU Calculator (3rd party product):

http://dtucalculator.azurewebsites.net

% Processor Time, Disk Reads/sec, Disk Writes/sec,
Log Bytes Flushed/sec
Monthly Cost (CAD)


Azure SQL Database (by DTUs)

Basic – 5 DTU – 2GB max storage – $7

Standard S3 – 100 DTU – 250GB max storage – $219

Premium P6 – 1000 DTU – 500GB max storage – $5,428

Premium P15 – 4000 DTU – 1TB max storage – $23,350
SQL Server on Azure Windows VM (by licence / resources)

DS13 instance (Web) – 8 cores – 56GB RAM – 400GB drive – $1,119

DS13 instance (Standard) – 8 cores – 56GB RAM – 400GB drive – $1,785

DS13 instance (Enterprise) – 8 cores – 56GB RAM – 400GB drive – $3,775

Additional storage – P30 SSD – 5,000 IOPS – 1TB – $164 per disk
Show Your Work

Compatibility tool (SSDT) → Can I even migrate to Azure SQL Database?

DTU Calculator → What service tier should I get? Do I need an elastic pool?

BACPAC EXPORT → Export database schema and data

BACPAC IMPORT → Insert database schema and data

Azure Portal → Look at the new precious
DTU Calculator (Cry Big Ugly Tears)

Important to capture over a busy period, for a long
enough period. BE REALISTIC!

First run of this tool, with 10 minutes of data, showed S3
($219/mo).

Second run of this tool, with an hour of data, showed P2
($1,357/mo).

Difference of $1,138 per month ($13,656 per year)
Acceptance

Your boss has approved the expense, so let’s migrate!
Tips and Tricks

Always use the latest version of SQL Server Management Studio

BACPAC files must be saved to standard Azure Blob Storage, not
premium

Make sure your database is compatible with SQL Server 2016 features

Watch out for hidden costs when scaling out SQL Databases, or running
VMs

Elastic pools can get expensive

De-allocate VMs, and delete databases, if not using them
Summary

DTUs do not map directly to resources, and require a workload to evaluate
against (time-based evaluation).

Some important on-premises features are not available in Azure SQL Database.

For smaller databases, web-based applications, and specifically new
development, Azure SQL Database may be appropriate.

SQL Server 2016 on Azure VM is more appropriate for existing applications, and
more cost-effective for larger databases, even with an Enterprise licence.

YMMV (your mileage may vary).
Credits

Azure website:


https://azure.microsoft.com/
Books Online:

https://technet.microsoft.com/enus/library/ms130214(v=sql.130).aspx