Showing posts with label weekend reading. Show all posts
Showing posts with label weekend reading. Show all posts

Friday, December 16, 2016

Interesting SQL related links for the week of Dec 16, 2016

Here are some interesting articles I read and tweeted about this past week, I think you will like these as well. If you are bored this weekend, some of these might be good for you to read

SQL Server + Python — What’s new

Python is one of the most popular and fastest-growing languages used today. Pyodbc (Python-SQL Server Connector) is an open source Python module maintained by Michael Kleehammer that uses ODBC Drivers to connect to SQL Server. It allows you to connect from the platform of your choice to SQL Server on-premises and in the cloud. Pyodbc is also cross platform and can be installed using pip.

We recently announced SQL Server v.Next CTP1 on Linux and Windows, which brings the power of SQL Server to both Windows and — for the first time ever — Linux. You can now connect your applications to SQL Server running on Linux, Windows and macOS (with Docker).

For our Python developers, we have a few updates that will improve Python connectivity with SQL Server. Pyodbc is now:

SQL Server 2016 SP1: Know your limits

With the recent announcement of SQL Server 2016 SP1, we announced the consistent programmability experience for developers and ISVs, who can now maintain a single code base and build intelligent database applications which scale across all the editions of SQL Server. The processor, memory and database size limits does not change and remain as–in all editions as documented in the SQL Server editions page. We have made the following changes in our documentation to accurately reflect the memory limits on lower editions of SQL Server. This blog post is intended to clarify and provide more information on the memory limits starting with SQL Server 2016 SP1 on Standard, Web and Express Editions of SQL Server.

Parameterization for Always Encrypted – Using SSMS to Insert into, Update and Filter by Encrypted Columns

SQL Server Management Studio 17.o (the next major update of SSMS, currently available as a Release Candidate) introduces two important capabilities for Always Encrypted:
  • Ability to insert into, update and filter by values stored in encrypted columns from a Query Editor window.
  • The new online encryption algorithm, exposed in the Set-SqlColumnEncryption PowerShell cmdlet, which makes tables available for both reads and writes during the initial encryption and column encryption key rotation.

This article addresses the first of the two enhancements.

While we often worry about sophisticated digital attacks, the most common attacks for accessing news organizations’ accounts depend on only a few simple weaknesses. These weaknesses are usually a combination of predictable passwords, phishing emails designed to steal login credentials, as well as malicious file attachments in email and elsewhere. While the attacks are simple, so are the defenses. This collection of resources and learning materials will walk you through practices recommended by security specialists for defending your newsroom against common attacks on your accounts.

SQL Server on Linux: How? Introduction

Making SQL Server run on Linux involves introducing what is known as a Platform Abstraction Layer (“PAL”) into SQL Server. This layer is used to align all operating system or platform specific code in one place and allow the rest of the codebase to stay operating system agnostic. Because of SQL Server’s long history on a single operating system, Windows, it never needed a PAL. In fact, the SQL Server database engine codebase has many references to libraries that are popular on Windows to provide various functionality. In bringing SQL Server to Linux, we set strict requirements for ourselves to bring the full functional, performance, and scale value of the SQL Server RDBMS to Linux. This includes the ability for an application that works great on SQL Server on Windows to work equally great against SQL Server on Linux. Given these requirements and the fact that the existing SQL Server OS dependencies would make it very hard to provide a highly capable version of SQL Server outside of Windows in reasonable time it was decided to marry parts of the Microsoft Research (MSR) project Drawbridge with SQL Server’s existing platform layer SQL Server Operating System (SOS) to create what we call the SQLPAL. The Drawbridge project provided an abstraction between the underlying operating system and the application for the purposes of secure containers and SOS provided robust memory management, thread scheduling, and IO services. Creating SQLPAL enabled the existing Windows dependencies to be used on Linux with the help of parts of the Drawbridge design focused on OS abstraction while leaving the key OS services to SOS. We are also changing the SQL Server database engine code to by-pass the Windows libraries and call directly into SQLPAL for resource intensive functionality.

Friday, December 09, 2016

Interesting SQL related links for the week of Dec 09, 2016

Here are some interesting articles I read and tweeted about this past week, I think you will like these as well. If you are bored this weekend, some of these might be good for you to read

Transaction Commit latency acceleration using Storage Class Memory in Windows Server 2016/SQL Server 2016 SP1

SQL Server 2016 SP1 adds a significant new performance feature, the ability to accelerate transaction commit times (latency) by up to 2-4X, when employing Storage Class Memory (NVDIMM-N nonvolatile storage). This scenario is also referred to as “persistent log buffer” as explained below.

This enhancement is especially valuable for workloads which require high frequency, low latency update transactions. These app patterns are common in the finance/trading industry as well as online betting and some process control applications.

As we all wind down for the 2016 holiday season, we want to give the SQL Server community a holiday gift to say ‘thank you’ for all your support during 2016, and what better gift than more free content?!

As many of you know, I publish a bi-weekly newsletter to more than 13,500 subscribers that contains an editorial on a SQL Server topic, a demo video, and a book review of my most recently completed book. We’re making all the 2015 demo videos available so everyone can watch them – 25 videos in all, mostly in WMV format. I did the same thing the last few years for the 2014 videos, 2013 videos, 2012 videos, and 2011 videos.

Developers Choice: Query progress – anytime, anywhere

One of the most important actions when a performance issue hits, is to get precise understanding on the workload that’s executing and how resource usage is being driven. The actual execution plan is an invaluable tool for this purpose.

Query completion is a prerequisite for the availability of an actual query plan, but with LQS (Live Query Statistics), you can already get information about in-flight query executions (see this blog post), which is especially useful for long running queries, and queries that run indefinitely and never finish.

To look at in-flight query executions, the query execution statistics profile infrastructure must be enabled on demand.

Get All of the Freebies for “End-to-End Troubleshooting Checklist for Microsoft SQL Server”

One of my most enduring and popular presentations is called End-to-End Troubleshooting Checklist for Microsoft SQL Server”. In this presentation, I take you through my six-step checklist from detection of a performance issue on SQL Server through identification of the root cause to remediation and finally post-mortem steps to ensure the problem is prevented (or at least detected immediately) in the future.

Over the years, I’ve had many inquiries about the slides, T-SQL scripts, and additional troubleshooting information. I’m happy to report that I’ve finally collated all of the associated content from that presentation!

Selective XML Indexes: Not Bad At All

So what is a Selective XML index? It’s an index! For XML! Where you pick the parts of the XML to index. Other XML indexes are rather all or nothing, and can end up being pretty huge, depending on the size of your documents. I think they’re at least size of data, if I recall correctly. Let’s take a look at some examples.


The sp_WhatsupQueryStore Stored Procedure is a Microsoft SQL Server Stored Procedure that retrieves all kinds of information from the Query Store. By running the script on this website the sp_WhatsupQueryStore Stored Procedure gets installed in the "master" database of your SQL Server Instance.

After installation you can run the Stored Procedure as follows:

EXEC sp_WhatsupQueryStore @dbname, @timewindow, @topqueries, @return_store_config, @return_forced_plans, @return_top_duration, @return_top_cpu, @return_top_log_read, @return_top_log_write, @return_top_phys_read

Clustered Columnstore Index in Azure SQL Database

Columnstore index is the preferred technology to run analytics queries in Azure SQL Databases. We recently announced general availability if In-Memory technologies for all Premium databases. Similar to In-Memory OLTP, the columnstore index technology is available in premium databases.

The columnstore technology is available in two flavors; clustered columnstore index (CCI) for DataMart analytics workloads and nonclustered columnstore index (NCCI) to run analytics queries on operational (i.e. OLTP) workload. Please refer to NCCI vs CCI for the differences between these two flavors of columnstore indexes. The columnstore index can speed up the performance of analytics queries up to 100x while significantly reducing the storage footprint. The data compression achieved depends on the schema and the data, but we see around 10x data compression on average when compared to rowstore with no compression. This blog will focus on Analytic workloads using CCI but cover NCCI in a future blog.

When Did SQL Server Last Update That Statistic? How Much Has Been Modified Since? And What Columns are in the Stat?

Whether I’m working as a DBA, a consultant, a teacher, or just answering questions in my inbox, I always end up needing a script to inspect statistics one way or another.

Here are some freshly written scripts for a classic DBA question: what’s going on in my stats?

SQL Server + Java: What’s new

Java continues to be one of the most widely used programming languages for a variety of application scenarios and industries. The Microsoft JDBC Driver for SQL Server is used to connect Java applications to SQL Server, whether SQL Server is hosted in the cloud or on-premises, or provided as a platform-as-a-service.

With the release of SQL Server v.Next public preview on Linux and Windows, the ability to connect to SQL Server on Linux, Windows, Docker or macOS (via Docker) makes cross-platform support for all connectors, including the JDBC driver, even more important. To enable Java developers to use the newest SQL Server features, we have been updating the JDBC driver with client-side support for new features, including Always Encrypted and Azure Active Directory Authentication.

Microsoft R Server 9.0 now available

Microsoft R Server 9.0, Microsoft's R distribution with added big-data, in-database, and integration capabilities, was released today and is now available for download to MSDN subscribers. This latest release is built on Microsoft R Open 3.3.2, and adds new machine-learning capabilities, new ways to integrate R into applications, and additional big-data support for Spark 2.0.

This release includes a brand new R package for machine learning: MicrosoftML. This package provides state-of-the-art, fast and scalable machine learning algorithms for common data science tasks including featurization, classification and regression. Some of the functions provided include:
  • Fast linear and logistic model functions based on the Stochastic Dual Coordinate Ascent method;
  • Fast Forests, a random forest and quantile regression forest implementation based on FastRank, an efficient implementation of the MART gradient boosting algorithm;
  • A neural network algorithm with support for custom, multilayer network topologies and GPU acceleration;
  • One-class anomaly detection based on support vector machines.
You can learn more about MicrosoftML at this live webinar on Wednesday, December 14.

Released: Public Preview for Microsoft Azure SQL Database Management Pack (

We are working on significantly updating the Management Pack for Azure SQL Database.

This release will bring support for Elastics Pools and Azure AD Authentication among other new features. We are also working on handling monitoring of larger number of databases. We are expecting to improve the scale by the time we RTM. Here are some numbers to give you an idea for this public preview:

Improve query performance on memory optimized tables with Temporal using new index creation enhancement in SP1

With the introduction of the Temporal feature in SQL 2016 and Azure SQL Database, there is an ability to time travel through the state of data as it was at any given point of time. Alongside In-Memory OLTP, Temporal on memory optimized tables allows you to harness the speed of In-Memory OLTP, and gives you the same ability to track history and audit every change made to a record. Temporal added to memory optimized tables also allows you to maintain a “smaller” memory optimized tables and thereby a smaller memory footprint by deleting data that isn’t “hot” anymore from the current memory optimized table, which in turn moves it to the history table without having an external archival process to do that.
When memory optimized and temporal tables are combined, an internal memory optimized table is created in addition to the history table, as depicted in the diagram below. Data is flushed asynchronously from the internal in-memory History table to the disk based history table. The flush interval  isn’t currently configurable. Data is flushed when the internal table reaches 8% of the memory consumed by the current table, OR you can flush it manually by executing the procedure sys.sp_xtp_flush_temporal_history. The internal memory optimized table is created with the same column definitions as the current in-memory table, but with a single index.

Extended per-operator level performance stats for Query Processing
As requested by the community to complete the per-operator information, starting with SQL Server 2016 SP1 we are now exposing memory grant per grant iterator (such as Sorts and Hash Matches). These give you added insight into memory grants, and how overall memory usage is driven throughout execution.
In the October release of SSMS we exposed per-operator stats directly in the Properties window for each operator, but the memory grant properties are not there yet. These will be added to the properties window in an upcoming release of SSMS

Friday, December 02, 2016

Interesting SQL related links for the week of Dec 02, 2016

Here are some interesting articles I read and tweeted about this past week, I think you will like these as well. If you are bored this weekend, some of these might be good for you to read

Microsoft is putting reprogrammable chips into millions of servers

All the Internet giants, including Microsoft, now supplement their CPUs with graphics processing units, chips designed to render images for games and other highly visual applications. When these companies train their neural networks to, for example, recognize faces in photos—feeding in millions and millions of pictures—GPUs handle much of the calculation

Some giants like Microsoft are also using alternative silicon to execute their neural networks after training. And even though it’s crazily expensive to custom-build chips, Google has gone so far as to design its own processor for executing neural nets, the tensor processing unit.

Developers choice: Programmatically identify LPIM and IFI privileges in SQL Server

Lock Pages in Memory and Instant File Initialization privileges are couple of configuration settings which every DBA, SQL Server consultant or enthusiast have it in their checklist to ensure they see a predictable performance for their SQL Server instance. While Lock Pages in Memory privilege information is logged in SQL Error log, Instant File initialization information was first introduced in SQL Errorlog starting SQL Server 2016 RTM and later added to SQL Server 2014 with SP2.

When you are managing, administering or monitoring large deployment of SQL Servers, it is still cumbersome to programmatically query SQL Error log to check if these permissions are enabled for the SQL Server service account. With SQL Server 2016 SP1, we have added new columns in the DMV which now makes it easy to develop scripts to programmatically query and report whether Lock Pages in Memory and instant file initialization privileges are enabled on a given instance of SQL Server.

Introducing Batch Mode Adaptive Memory Grant Feedback

SQL Server uses memory to store in-transit rows for hash join and sort operations. When a query execution plan is compiled for a statement, SQL Server estimates both the minimum required memory needed for execution and the ideal memory grant size needed to have all rows in memory. This memory grant size is based on the estimated number of rows for the operator and the associated average row size. If the cardinality estimates are inaccurate, performance can suffer:

  • For cardinality under-estimates, the memory grant can end up being too small and the rows then spill to disk, causing significant performance degradation compared to a fully memory-resident equivalent.
  • For cardinality over-estimates, the memory grant can be too large and the memory goes to waste. Concurrency can be impacted because the query may wait in a queue until enough memory becomes available, even though the query only ends up using a small portion of the granted memory.

SQL Server on Linux: High availability and security

With SQL Server on Linux, Microsoft brings SQL Server’s core relational database engine to the growing enterprise Linux ecosystem. Both High Availability and Disaster Recovery (HADR) and security are aspects of SQL Server that are critically important for enterprises. This article highlights the HADR and security solutions for SQL Server on Linux that are available today, as well as the roadmap for what’s coming soon.

Using SQL Tools with SQL Server on Linux

Today, developers can use SQL Server in a variety of environments including on-premises, in datacenters, in virtual machines, in clouds such as Azure, AWS and Google, and also as a Platform as a Service (PaaS) offering with Azure SQL Database and Azure SQL Data Warehouse.

We recently announced SQL Server v.Next CTP1 on Linux and Windows, which brings the power of SQL Server to both Windows — and for the first time ever — Linux. Developers can now create applications with SQL Server on Linux, Windows, Docker, or macOS (via Docker) and then deploy to Linux, Windows, or Docker, on-premises or in the cloud.

As part of this announcement, we have released new SQL tools and also updated existing SQL tools. Developers can use these tools to connect to and work with SQL running anywhere, including SQL Server on Linux, Windows or Docker.

Reading 7 Things I Learned About Aurora at AWS re:Invent 2016

Richie and I attended the AWS re:Invent conference in Vegas last week. Here’s some of my favorite takeaways about Amazon Aurora, their homegrown relational database with MySQL compatibility.

Friday, November 25, 2016

Interesting SQL related links for the week of Nov 25, 2016

Here are some interesting articles I read and tweeted about this past week, I think you will like these as well. If you are bored this weekend, some of these might be good for you to read

Released: Public Preview for System Center Management Packs for SQL Server

We are getting ready to update the SQL Server Management Packs family. Please install and use this public preview and send us your feedback (! We appreciate the time and effort you spend on these previews which make the final product so much better.
Please download at:
Included in the download are:
  • Microsoft System Center Management Pack for SQL Server 2008/2008 R2/2012/2014/2016 (
  • Microsoft System Center Management Pack for SQL Server Replication 2008/2012/2014/2016 (
  • Microsoft System Center Management Pack for SQL Server Analysis Services 2008/2012/2014/2016 (
  • Microsoft System Center Management Pack for SQL Server Reporting Services 2008/2012/2014/2016 (
  • Microsoft System Center Management Pack for SQL Server Dashboards (

SQL Server 2016 SP1: Known issues

The SQL Product team has identified the following known issues which the customers may encounter after installing SQL Server 2016 SP1. The following post will help the customers  plan and prepare their environment for the following known issues while installing SQL Server 2016 SP1.

Index Scans: Not Nearly As Bad As You Might Think

Using our good old buddy the StackOverflow demo database, let’s look at the Users table. I want to get the first 10 users in the table ordered by Id, the primary clustered key, which is an identity field.

Ooo – clustered index scan – that’s bad, right?

Not so fast. Click on the plan to view it in, and hover your mouse over the Clustered Index Scan:

Source Control in SQL Server Management Studio (SSMS)

In the latest generation of SQL Server Management Studio, we moved to the Visual Studio 2015 Isolated Shell. While this provides SSMS a modern IDE foundation for many functional areas, it also had some consequences. Specifically, the integration with source control systems in SSMS no longer works the way it did in SSMS 2014 and prior.  Previously, one could install the Visual Studio MSSCCI provider and then integrate with various source control systems. Visual Studio 2015 does not support MSSCCI so that is no longer an option to use in SSMS.
Of course, the good news is that Visual Studio 2015 includes TFS and Git source control integration. With the move to VS 2015 Isolated Shell, SSMS should be able to use these packages as well, right? The answer is…yes…but! The issue for SSMS is that the TFS source control integration package VS provides also includes the entire suite of TFS integration features. If we include this package by default, SSMS will have Team Explorer in its entirety which includes things such as work item tracking, builds, etc. This doesn’t fit in the overall experience SSMS is designed for, so we aren’t going to include this package as part of SSMS. The full TFS integrated experience is included as part of SQL Server Data Tools which is designed for a more developer-centric set of scenarios.
That said, if source code integration is an important aspect of how you use SSMS, you can enable the Visual Studio packages manually.

Why is My Query Faster the Second Time it Runs? (Dear SQL DBA Episode 23)

Whenever I create a complex view, the first time I use it in a query, the query is slow. The same thing happens after I alter the view. What is the reason behind this?
This is a great question — because when you ask this question, you’re about to discover a lot of interesting, useful things about how SQL Server runs queries.
There are two ways that SQL Server can use memory to make a query faster the second time you run it. Let’s talk about how the magic happens.

Friday, November 18, 2016

Interesting SQL related links for the week of Nov 18, 2016

Here are some interesting articles I read and tweeted about this past week, I think you will like these as well. If you are bored this weekend, some of these might be good for you to read

Massive Disruption Is Coming With Quantum Computing
Next year, we may see the launch of the first true quantum computers.

The implications will be staggering.

This post aims to answer three questions:
  1. What are quantum computers?
  2. What are their implications?
  3. Who’s working on them?

New Showplan XML properties in SSMS October Release

Back in March we announced the availability of per-operator level performance stats for Query Processing (exposed in Showplan XML) with SQL Server 2014 SP2 and SQL Server 2016. However, SQL Server Management Studio (SSMS) did not expose this information, and so users had to look in the Showplan XML, in the context of the appropriate node and operator.

This caused some friction, and so we are happy to announce that in the latest (October) release of SSMS, these attributes are now readily available in the Properties window of an Actual Execution Plan, in the scope of each operator.

Microsoft signs deal to power data center entirely by wind power

You need a lot of energy to run a data center. Especially when your name is Microsoft, and you’re the biggest technology company on the planet. But this doesn’t necessarily have to be environmentally harmful.

The company just announced that it has inked deals with two wind farms, with the aim of entirely powering its Cheyenne, Wyoming data center from renewable sources.

Microsoft has contracted Bloom Wind farm in Kansas to provide 178 megawatts, and the Silver Sage and Happy Jack farms in Wyoming to provide an additional 59 megawatts.

Unable to drop a user in a database

A user called in for help because he wasn’t able to drop a user from a database. The error message is below

Msg 15136, Level 16, State 1, Line 2
The database principal is set as the execution context of one or more procedures, functions, or event notifications and cannot be dropped.

From the error, the logical starting point is sys.sql_modules because functions, stored procedures have entries in this catalog view. Additionally, it has a column called execute_as_principal_id

So I looked there but found no entries whose execute_as_principal_id is the same user id of the user this customer tried to drop. Next I started to look at source code and found out this error is raised in a couple of other places. It gave me the clue that I didn’t have to do source code research, TSQL is all I needed to solve the problem.

Connect(); // 2016

Videos from the Connect(); // 2016 event can be found here
Screenshot of some of these

SQL Server 2016 Service Pack 1 (SP1) released !!!

With cloud first strategy, the SQL Product Team has observed great success and adoption of SQL Server 2016 compared to any previous releases. Today, we are even more excited and pleased to announce the availability of SQL Server 2016 Service Pack 1 (SP1). With SQL Server 2016 SP1, we are making key improvements allowing a consistent programmability surface area for developers and organizations across SQL Server editions. This will enable you to build advanced applications that scale across editions and cloud as you grow. Developers and application partners can now build to a single programming surface when creating or upgrading intelligent applications, and use the edition which scales to the application’s needs.

In addition to a consistent programmability experience across all editions, SQL Server 2016 SP1 also introduces all the supportability and diagnostics improvements first introduced in SQL 2014 SP2, as well as new improvements and fixes centered around performance, supportability, programmability and diagnostics based on the learnings and feedback from customers and SQL community.

SQL Server 2016 SP1 also includes all the fixes up to SQL Server 2016 RTM CU3 including Security Update MS16–136.

SQL Server on Linux Documentation
SQL Server vNext CTP1 now runs on Linux! Learn about the core relational database capabilities in this release of SQL Server, and how to install, manage, secure, and develop for this new release.

What's New in SQL Server vNext

SQL Server vNext represents a major step towards making SQL Server a platform that enables choices of development languages, data types, on-premises and in the cloud, and across operating systems by bringing the power of SQL Server to Linux, Linux-based Docker containers, and Windows.

You can find all the new stuff at that page

Now pay attention to the next two links... did you noticed it was getting colder since Wednesday? That is because Hell just froze over!!!!
A funny comment on slashdot
Microsoft joins the Linux foundation, Google joins the .NET foundation. What's next? Hillary joins the Trump Foundation?

Google Cloud to join .NET Foundation Technical Steering Group

Google is pleased to be joining the Technical Steering Group of the .NET Foundation. .NET is a key component in the modern enterprise, and the Google Cloud Platform (GCP) team has worked hard to ensure that .NET has first-class support on Google’s infrastructure, including excellent infrastructure for Windows. For years, Google has offered .NET libraries for more than 200 of its cloud services. More recently, we’ve built native GCP support for Visual Studio and PowerShell.

Come again?
Microsoft Fortifies Commitment to Open Source, Becomes Linux Foundation Platinum 

The Linux Foundation, the nonprofit advancing professional open source management for mass collaboration, today announced that Microsoft has joined the organization at a Platinum member during Microsoft’s Connect(); developer event in New York.

From cloud computing and networking to gaming, Microsoft has steadily increased its engagement in open source projects and communities. The company is currently a leading open source contributor on GitHub and earlier this year announced several milestones that indicate the scope of its commitment to open source development. The company released the open source .NET Core 1.0; partnered with Canonical to bring Ubuntu to Windows 10; worked with FreeBSD to release an image for Azure; and after acquiring Xamarin, Microsoft open sourced its software development kit. In addition, Microsoft works with companies like Red Hat, SUSE and others to support their solutions in its products.

Disable CREATE OR ALTER for DDL triggers (or fix it)
I filed this bug while working on the post What's new in SQL Server 2016: CREATE OR ALTER

On SQL Server 2016 SP1 and SQL Server vNext (neither available from drop down, so I picked 2016 RTM) When executing CREATE OR ALTER with a DDL trigger, it will run fine the first time, when you execute the script again, you will get an error like the following 

Msg 2714, Level 16, State 2, Procedure safety, Line 1 [Batch Start Line 77] There is already an object named 'safety' in the database. 

So either don't allow CREATE OR ALTER when the trigger is a DDL trigger or fix it so it doesn't throw the error if you run it more than once

And to finish it of, here are some of my blog posts about SQL Server vNext and SQL Server 2016 Service Pack 1 from this week

SQL Server 2016 SP1 released, SQL Server vNext available for download

Friday, November 11, 2016

Interesting SQL related links for the week of Nov 11, 2016

Here are some interesting articles I read and tweeted about this past week, I think you will like these as well. If you are bored this weekend, some of these might be good for you to read

.Net 4.6.2. Framework client driver for Always Encrypted resulting in intermittent failures to decrypt individual rows

The SQL Product team has identified an issue with .Net 4.6.2 framework client driver for Always Encrypted enabled database on SQL Server 2016 and Azure SQL Database. The issue can lead to intermittent failure while trying to decrypt the records from the Always Encrypted enabled database with following error message
Decryption failed. The last 10 bytes of the encrypted column encryption key are: ‘7E-0B-E6-D3-39-CE-35-86-2F-AA’.The first 10 bytes of ciphertext are: ’01-C3-D7-39-33-2F-E6-44-C3-B1′.Specified ciphertext has an invalid authentication tag. 

In-Memory OLTP: Is your database just in memory or actually optimized for memory?

In my many conversations with customers during Microsoft events, people often confuse between the terms ‘In Memory’ and ‘Memory-Optimized’ and many think that they are one and the same. If you continue reading this blog, you will realize that they are somewhat related but can lead to very different performance/scalability.

Paper Review: Why Does the Cloud Stop Computing? Lessons from Hundreds of Service Outages

This paper conducts a cloud outage study of 32 popular Internet services, and analyzes outage duration, root causes, impacts, and fix procedures. The paper appeared in SOCC 2016, and the authors are Gunawi, Hao, Suminto Laksono, Satria, Adityatama, and Eliazar.

Availability is clearly very important for cloud services. Downtimes cause financial and reputation damages. As our reliance to cloud services increase, loss of availability creates even more significant problems. Yet, several outages occur in cloud services every year. The paper tries to answer why outages still take place even with pervasive redundancies.

Daniel H Pink: employees are faster and more creative when solving other people's problems

Recent research reveals that people are more capable of mental novelty when thinking on behalf of others than for themselves. This has far-reaching practical implications at every level of business.

I’ve gotten a few questions about shrinking SQL Server data files lately. What’s the best way to get shrink to run? And why might it fail in some cases?

Traditionally, every time you ask a DBA how to make shrinking suck less, they start ranting how shrinking is bad and you just shouldn’t do it. Sometimes it sounds kinda angry.

What people are trying to say is that shrinking data files is generally slow, frustrating, and painful for you.

How It Works (It Just Runs Faster): Non-Volatile Memory SQL Server Tail Of Log Caching on NVDIMM

SQL Server 2016 has been enhanced along with Windows 2016 to detect a direct access volume (/dax.) When you create or alter the SQL Server database you simply add the LOG ON clause, pointing to the DAX enabled volume. SQL Server will detect the request on the DAX based volume and create the non-volatile, tail of log cache of fixed size for the database. From all external aspects (DMVs for example) the tail of log cache looks like another file that is part of the database’s LOG file group.

NASA Is Harnessing Graph Databases To Organize Lessons Learned From Past Projects

NASA famously maintains a "lessons learned" database containing valuable information from its past programs and projects. But the vast system, which has been online since 1994, is not always easy to navigate. Now the agency is modernizing it with help from a tool more familiar to social media than space missions: graph databases.

The genesis of the change began about a year and a half ago when an engineer, attempting to search "lessons learned" for relevant documents, found the number of possible results overwhelming. "He was getting things that really were not relevant to what he was looking for," David Meza, NASA’s chief knowledge architect, recalls.

Looking to make the database more useful, and help users investigate relationships beyond what basic keyword searches could uncover, Meza experimented with storing the information in a graph database—that is, a database optimized to store information in terms of data records and the connections between them. In recent years, such network graphs have become a familiar feature of online social networks.

Microsoft Azure SQL Database provides unparalleled performance with In-Memory technologies

Azure SQL Database built-in In-Memory technologies are now generally available for the Premium database tier including Premium pools. In-memory technology helps optimize the performance of transactional (OLTP), analytics (OLAP), as well as mixed workloads (HTAP). These technologies allow you to achieve phenomenal performance with Azure SQL Database – 75,000 transactions per second for order processing (11X perf gain) and reduced query execution time from 15 seconds to 0.26 (57X perf). You can also use them to reduce cost – on a P2 database obtain 9X perf gain for transactions or 10X perf gain for analytics queries by implementing In-Memory technologies, without any additional cost!

Offshoring roulette: lessons from outsourcing to India, China and the Philippines

In what is now a former life, I spent a great deal of time sending work overseas. In fact, I spent quite a bit of time over there myself in some of the places I'm going to talk about. That former life was as a software architect for Pfizer and in the last half dozen years of my 14-year tenure, I had responsibility for software architecture in the Asia Pacific region. For those not from this corner of the world, Asia Pacific is a sizeable chunk of the globe

TDD Doesn't Work

TDD Doesn't work.

It doesn't? That's odd. I've always found it to work quite well.

Not according to a new study.

Another study?

Yeah, an in-depth study that repeated another study that was done a few years back. Both showed that TDD doesn't work. The new one uses a multi-site, blind analysis, approach. It looks conclusive.

Oops Recovery with Temporal Tables

Have you ever got that sinking feeling after hitting the Execute button in SSMS, thinking “I should not have done that”? DML statements with missing WHERE clause, DROP statements accidentally targeting slightly mistyped (but existing) tables or databases, RESTORE statements overwriting databases with new data that haven’t been backed up, are all examples of actions prompting an “Oops…” (or worse) shortly thereafter. “Oops recovery” is the term that became popular to describe the process of fixing the consequences.

For most of these scenarios, the usual, and often the only, recovery mechanism is to restore the database from backup to a point in time just before the “oops”, known as point-in-time recovery (PITR). Even though PITR remains the most general and the most effective recovery mechanism, it does have some drawbacks and limitations: the recovery process requires a full database restore, taking the time proportional to the size of the database; a sequence of restores may be needed if multiple “oops” transactions have occurred; in the general case, there will be difficulties reconciling recovered data with data modified after the “oops” point in time, etc. Nevertheless, PITR remains the most widely applicable recovery method for SQL Server databases, both on-premises and in the cloud.

Introduction to Machine Learning for Developers

Today’s developers often hear about leveraging machine learning algorithms in order to build more intelligent applications, but many don’t know where to start.

One of the most important aspects of developing smart applications is to understand the underlying machine learning models, even if you aren’t the person building them. Whether you are integrating a recommendation system into your app or building a chat bot, this guide will help you get started in understanding the basics of machine learning.

This introduction to machine learning and list of resources is adapted from my October 2016 talk at ACT-W, a women’s tech conference.

And that is all for this week, try to read some of these over the weekend....