Thursday, February 21, 2008

46 New Dynamic Management Views In SQL Server 2008 CTP6

Remember the 33 new DMVs in SQL Server 2008 post? I was just poking around in SQL Server 2008  CTP6 and wanted to know if there were any new Dynamic Management Views since CTP5. There are 13 new DMVs in CTP6 and there are a total of 45 new Dynamic Management Views compared to SQL server 2005. The list of them is below, I think their names make clear what the dmv is supposed to do (or at least I think I know)




dm_audit_actions
dm_audit_class_type_map
dm_cdc_errors
dm_cdc_log_scan_sessions
dm_cryptographic_provider_algorithms
dm_cryptographic_provider_keys
dm_cryptographic_provider_properties
dm_cryptographic_provider_sessions
dm_database_encryption_keys
dm_db_mirroring_auto_page_repair
dm_db_mirroring_past_actions
dm_db_persisted_sku_features
dm_exec_procedure_stats
dm_exec_trigger_stats
dm_filestream_oob_handles
dm_filestream_oob_requests
dm_fts_fdhosts
dm_fts_index_keywords
dm_fts_index_keywords_by_document
dm_fts_outstanding_batches
dm_fts_parser
dm_os_dispatcher_pools
dm_os_dispatchers
dm_os_memory_brokers
dm_os_memory_node_access_stats
dm_os_memory_nodes
dm_os_nodes
dm_os_process_memory
dm_os_spinlock_stats
dm_os_sys_memory
dm_resource_governor_configuration
dm_resource_governor_resource_pools
dm_resource_governor_workload_groups
dm_server_audit_status
dm_sql_referenced_entities
dm_sql_referencing_entities
dm_tran_commit_table
dm_xe_map_values
dm_xe_object_columns
dm_xe_objects
dm_xe_packages
dm_xe_session_event_actions
dm_xe_session_events
dm_xe_session_object_columns
dm_xe_session_targets
dm_xe_sessions



The 13 DMVs listed below are new in CTP6



dm_audit_actions
dm_audit_class_type_map
dm_db_persisted_sku_features
dm_exec_procedure_stats
dm_exec_trigger_stats
dm_fts_fdhosts
dm_fts_index_keywords
dm_fts_index_keywords_by_document
dm_fts_outstanding_batches
dm_fts_parser
dm_os_dispatchers
dm_os_memory_node_access_stats
dm_server_audit_status



If you want to find out what the names of all the new DMVs are by running a query on your SQL Server 2008 box and you don't have a linked server to a SQL Server 2005 box then don't worry I have prepared the query below for you.


 
SELECT * FROM sysobjects
WHERE name LIKE 'dm_%'
AND name NOT IN('dm_os_hosts',
'dm_exec_cached_plan_dependent_objects',
'dm_os_memory_allocations',
'dm_os_loaded_modules',
'dm_db_task_space_usage',
'dm_os_memory_objects',
'dm_os_schedulers',
'dm_os_threads',
'dm_exec_requests',
'dm_db_missing_index_columns',
'dm_repl_tranhash',
'dm_qn_subscriptions',
'dm_db_session_space_usage',
'dm_exec_query_optimizer_info',
'dm_tran_top_version_generators',
'dm_os_waiting_tasks',
'dm_exec_background_job_queue',
'dm_exec_cursors',
'dm_db_missing_index_details',
'dm_clr_properties',
'dm_os_sublatches',
'dm_exec_query_memory_grants',
'dm_tran_current_snapshot',
'dm_io_virtual_file_stats',
'dm_exec_xml_handles',
'dm_os_wait_stats',
'dm_exec_text_query_plan',
'dm_broker_connections',
'dm_os_stacks',
'dm_os_ring_buffers',
'dm_db_missing_index_groups',
'dm_exec_cached_plans',
'dm_exec_sessions',
'dm_broker_forwarded_messages',
'dm_os_memory_clerks',
'dm_repl_articles',
'dm_fts_memory_buffers',
'dm_fts_index_population',
'dm_tran_current_transaction',
'dm_os_child_instances',
'dm_exec_connections',
'dm_exec_background_job_queue_stats',
'dm_fts_active_catalogs',
'dm_tran_database_transactions',
'dm_os_memory_cache_clock_hands',
'dm_repl_schemas',
'dm_db_mirroring_connections',
'dm_db_index_operational_stats',
'dm_db_partition_stats',
'dm_io_pending_io_requests',
'dm_os_memory_cache_entries',
'dm_os_virtual_address_dump',
'dm_tran_transactions_snapshot',
'dm_exec_query_plan',
'dm_os_memory_cache_hash_tables',
'dm_exec_query_stats',
'dm_clr_tasks',
'dm_os_worker_local_storage',
'dm_db_index_usage_stats',
'dm_db_index_physical_stats',
'dm_os_buffer_descriptors',
'dm_tran_active_snapshot_database_transactions',
'dm_tran_active_transactions',
'dm_db_file_space_usage',
'dm_broker_activated_tasks',
'dm_broker_queue_monitors',
'dm_os_memory_cache_counters',
'dm_tran_session_transactions',
'dm_clr_appdomains',
'dm_exec_sql_text',
'dm_os_memory_pools',
'dm_os_latch_stats',
'dm_io_backup_tapes',
'dm_fts_memory_pools',
'dm_os_sys_info',
'dm_tran_locks',
'dm_exec_query_transformation_stats',
'dm_exec_query_resource_semaphores',
'dm_repl_traninfo',
'dm_db_missing_index_group_stats',
'dm_fts_population_ranges',
'dm_os_performance_counters',
'dm_os_workers',
'dm_io_cluster_shared_drives',
'dm_os_tasks',
'dm_exec_plan_attributes',
'dm_tran_version_store',
'dm_os_cluster_nodes',
'dm_clr_loaded_assemblies')

Enjoy exploring these DMVs



 



 


Wednesday, February 20, 2008

Microsoft SQL Server 2008 Feature Pack CTP, February 2008

The Feature Pack is a collection of stand-alone install packages that provide additional value for SQL Server 2008. It includes the latest versions of:

Redistributable components for SQL Server 2008
Add-on providers for SQL Server 2008
Backward compatibility components for SQL Server 2008

Microsoft SQL Server 2008 Native Client
Microsoft SQL Server 2008 Native Client (SQL Native Client) is a single dynamic-link library (DLL) containing both the SQL OLE DB provider and SQL ODBC driver. It contains run-time support for applications using native-code APIs (ODBC, OLE DB and ADO) to connect to Microsoft SQL Server 2000, 2005, or 2008. SQL Native Client should be used to create new applications or enhance existing applications that need to take advantage of new SQL Server 2008 features. This redistributable installer for SQL Native Client installs the client components needed during run time to take advantage of new SQL Server 2008 features, and optionally installs the header files needed to develop an application that uses the SQL Native Client API.


Microsoft SQL Server 2005 Backward Compatibility Components
The SQL Server Backward Compatibility package includes the latest versions of Data Transformation Services 2000 runtime (DTS), SQL Distributed Management Objects (SQL-DMO), Decision Support Objects (DSO), and SQL Virtual Device Interface (SQLVDI). These versions have been updated for compatibility with both SQL Server 2005 and SQL Server 2008 and include all fixes shipped through SQL Server 2000 SP4 and SQL Server 2005 SP2.

Microsoft SQL Server 2008 Reporting Services Add-in for Microsoft SharePoint Technologies
Microsoft SQL Server 2008 Reporting Services Add-in for SharePoint Technologies allows you to take advantage of SQL Server 2008 report processing and management capabilities in SharePoint integrated mode. This version also includes data-driven subscriptions. The download provides a Report Viewer web part, web application pages, and support for using standard Windows SharePoint Services or Microsoft Office SharePoint Services.

Get it all here: http://www.microsoft.com/downloads/details.aspx?FamilyId=D68DE3C9-60A9-49C9-A28C-5C46BBC3356F&displaylang=en

SQL Server 2008 February CTP is now available for public download

SQL Server 2008 February CTP is finally here, this CTP is supposed to be feature complete.

Download the February CTP from the Download Center!

What's New in SQL Server 2008 February CTP?

Enter to win an Xbox in the SQL Server 2008 February CTP Bug Bash!

Monday, February 18, 2008

If Airplanes Were Made By Using Scrum/Agile

So I have been doing Scrum for a while now, I came across this video and thought it was hilarious. When you do Scrum you develop by using sprints, a sprint is usually between 2 and 4 weeks and at the end of the sprint you should have something working that you can show to the client/business unit

Watch the video



If someone is interested in a high level post about Scrum then leave a comment and I will post something next week

Sunday, February 17, 2008

Weekly Links 20080217

I decided to do a weekly links post with interesting SQL Server stuff, I also include a bunch of funny things at the bottom.

Technical Stuff:
Bob Beauchemin has two post that deal with Spatial Data: Using SQL Server 2008 spatial and the Virtual Earth map control - 1 and Using SQL Server 2008 spatial and the Virtual Earth map control - 2. The Spatial Data posts are more for people who do front end as well as back end development.
Two Interesting articles by the PSS SQL Server Engineers
How it Works: SQL Server Per Query Degree Of Parallelism Worker Count(s) and How It Works: SQL Server 2005 Connection and Task Assignments
Kalen Delany's Geek City: String Statistics post. My own Functions That Are Not Often Used: SIGN from sqlblog. Amdahl’s Law by Linchi Shea

If that is not enough for you there are also a bunch of SQL Server 2008 Webcasts available as well as a bunch of SQL Server 2008 Videos.

The non technical stuff:
Like Father Like Grandson
I had friends...
Pronounce this if you can
Peek into offices at LinkedIn, Flickr & Facebook

HTTP Endpoints deprecated In SQL Server 2008, Just Like Notification Services

Just like Notification Services HTTP Endpoints have been deprecated in SQL Server 2008. Bob Beauchemin's Blog has more info here: HTTP Endpoints to be deprecated in SQL Server 2008

Thursday, February 14, 2008

SQL Server 2008 Whitepapers

General
SQL Server 2008 Product Overview
Microsoft® SQL Server™ provides a policy-based system for managing one or more instances of SQL Server along with tools for performance monitoring, troubleshooting, and tuning that enable administrators to more efficiently manage their databases and SQL Server instances.
Focus: What's New
Audience: High-level

Business Intelligence
An Introduction to New Data Warehouse Scalability Features in SQL Server 2008
With the 2008 release, SQL Server makes a major advance in scalability for data warehousing. It meets the data warehouse needs of the largest enterprises more easily than ever. SQL Server 2008 provides a range of integrated products that enable you to build your data warehouse, and query and analyze its data. These include the SQL Server relational database system, Analysis Services, Integration Services, and Reporting Services. This paper introduces the new performance and manageability features for data warehousing across all these components. All these features contribute to improved scalability.
Audience: High-level

SQL Server 2008 Analysis Services Overview
Microsoft SQL Server 2008 Analysis Services builds on the value delivered with the significant investments in Analysis Services 2005 around scalability, advanced analytics and Microsoft Office interoperability. This paper covers a high-level look at the key Analysis Services features available in SQL Server 2008.
Audience: High-level

Predictive Analysis with SQL Server 2008
This 10-page paper explores the complete and intuitive set of data mining tools offered in Microsoft SQL Server 2008: Predictive Analysis for All Users, Insight at Every Step of the Data Lifecycle, and Data Mining Awareness in Every Application.
Audience: High-level

Business Intelligence in SQL Server 2008
This 10-page paper includes: Introduction, Unifying Data Storage and Access, Building and Managing Sophisticated BI Solutions, Extending the Reach of Your BI Solution, and Conclusion.Focus: Business Intelligence
Audience: High-level

SQL Server 2008 Reporting Services Whitepaper
This paper discusses how Microsoft SQL Server 2008 Reporting Services provides a complete server-based platform that is designed to support a wide variety of reporting needs including managed enterprise reporting, ad-hoc reporting, embedded reporting, and web based reporting to enable organizations to deliver relevant information where needed across the entire enterprise.Focus: Reporting Services
Audience: High-level

An Introduction to SQL Server 2008 Integration ServicesThis paper discusses the challenges that face businesses that rely on data integration technologies to provide meaningful, reliable information to maintain a competitive advantage in today’s business world. It discusses how SQL Server 2008 Integration Services (SSIS) can help Information Technology departments meet data integration requirements in their companies. Real-world scenarios are included.Focus: Integration Services
Audience: High-level Data Warehousing

Choosing SQL Server 2008 for Data Warehousing
This 10-page paper discusses: The State of Data Warehousing, The Realities of Data Warehousing Today, Putting the Technology Set Together, and Rounding It Out.Focus: Data Warehousing
Audience: High-level


Application Development/Data Programmability
Microsoft SQL Server 2008 and Microsoft Data Platform Development
This 10-page paper includes: Improved Productivity through ADO.NET Entity Framework, LINQ, and Visual Studio, Comprehensive Data Platform, and Scalable Data-Centric Solutions.
Focus: Developer Productivity
Audience: Technical

What's New for XML in SQL Server 2008?
A 16-page paper that discusses how Microsoft SQL Server 2008 builds on the extensive support for XML by extending support for XML schema validation and XQuery, and by enhancing the xml data type.
Focus: XML
Audience: Technical

Managing Unstructured Data with SQL Server 2008
This 11-page paper discusses how Microsoft SQL Server™ 2008 provides a flexible solution for storing unstructured data and combining it with relational data to build comprehensive solutions that encompass the full range of data across an organization.
Focus: Unstructured Data
Audience: Technical

SQL Server 2008: Delivering Location Intelligence with Spatial Data
This 10-page paper discusses how the new spatial support in Microsoft SQL Server™ 2008 can help you to make better decisions through visual analysis of location data that can be stored and manipulated in a SQL Server database.
Focus: Spatial Data
Audience: Mid-level

Online Transaction Processing/Data Management
SQL Server 2008 Security Overview for Database Administrators
SQL Server 2008 is secure by design, default, and deployment. Microsoft is committed to communicating information about threats, countermeasures, and security enhancements as necessary to keep your data as secure as possible. This paper covers some of the most important security features in SQL Server 2008. It tells you how, as an administrator, you can install SQL Server securely and keep it that way even as applications and users make use of the data stored within.
Focus: Security
Audience: Mid-level

Online Transaction Processing in SQL Server 2008
This 10-page paper includes: Introduction, Scale and Performance, High Availability, Security, and Manageability.
Focus: OLTP
Audience: High-level

SQL Server 2008 Manageability
This paper discusses how Microsoft SQL Server 2008 builds on the management capabilities of previous versions and provides a variety of tools and frameworks to help you manage your enterprise data environment.
Focus: Manageability
Audience: High-level

SQL Server 2008 Performance and Scale
This paper discusses how Microsoft SQL Server 2008 incorporates the tools and technologies that are necessary to implement relational databases, reporting systems, and data warehouses of enterprise scale, and provides optimal performance and responsiveness.
Focus: Scale and Performance
Audience: Mid-level

Server Consolidation
Server Consolidation with SQL Server 2008
This 10-page paper includes: Introduction, Flexibility, Manageability, Scalability and Performance, and Conclusion.
Focus: Server Consolidation
Audience: High-level

Thursday, February 07, 2008

SQL Server 2008: When Was The Server Last Started?

SQL Server 2008 has an additional column in the sys.dm_os_sys_info Dynamic Management View. The name of the column is sqlserver_start_time and it will be the time SQL Server was last restarted

SELECT sqlserver_start_time FROM sys.dm_os_sys_info

Review of Inside Microsoft SQL Server 2005 Query Tuning and Optimization

SQL performance tuning is probably one of those things you can do to really make a HUGE difference in performance. Let’s put this in perspective: take a typical application, if you can improve the performance by 100% then you really made a huge improvement. You can improve a SQL query by 1000% with 2 lines of code (sometimes all you have to do is take away a % sign). If you can make a query sargable so that the optimizer can do an index seek instead of an index scan your query might go from 12 seconds to 200 milliseconds. Now try doing that in an application, even if you change all the string concatenation to use a stringbuilder instead of creating new strings all the time you will not get such a drastic performance improvement. I am sure you get the point by now, let’s talk about the book.

Inside Microsoft SQL Server 2005: Query Tuning and Optimization is part 4 of the Inside Microsoft SQL Server 2005 series, it is written by Kalen Delaney and five other authors. There are 6 chapters in this book

1 A Performance Troubleshooting Methodology

This chapter explains some typical things that affect performance and also gives a troubleshooting overview


2 Tracing and Profiling

This chapter explains how to use the profiler and how to analyze traces. SQL Server’s built-in traces are also covered


3 Query Execution

This chapter gives a query processing and execution overview. It explains how to read plans and goes into a lot of detail about analyzing plans


4 Troubleshooting Query Performance

This chapter explains how to detect problems in plans, how to improve queries and some best practices


5 Plan Caching and Recompilation

This chapter goes into detail about plan caching and recompilation and how to troubleshoot plan cache issues


6 Concurrency Problems

The final chapter deals with concurrency (locking, blocking and deadlocking)



This is an excellent book for an intermediate/advanced developer. There is so much new stuff in SQL Server 2005 compared to 2000 to help you with tuning queries that you probably want to read each chapter several times. The Dynamic Management Views are a big help and this book shows you how to use them. Some other cool stuff in this book is the discussion of internal tables, undocumented DBCC commands and undocumented trace flags to discover information which could help you determine much faster what the cause of a performance problem might be.
Some pages are packed with so much information that you need to pause for a second and process all that info (I have read some pages two to three times in a row). You will also find out that there are more joins besides left, full and outer. Page 137 for example has a nice table with the three Physical Join Operators: Nested Loop Join, Hash Join and Merge Join. This table lists the characteristics for each of these joins.

If you are an intermediate to advanced developer then I highly recommend this book. I have interviewed Kalen a while back about this book and you can find that interview here
http://sqlservercode.blogspot.com/2007/10/interview-with-kalen-delaney-about.html

Wednesday, February 06, 2008

33 New Dynamic Management Views In SQL Server 2008

I was just poking around in SQL Server 2008 and wanted to know if there were any new Dynamic Management Views. There are a total of 33 new Dynamic Management Views. The list of them is below, I think their names make clear what the dmv is supposed to do (or at least I think I know)


dm_cdc_errors
dm_cdc_log_scan_sessions
dm_cryptographic_provider_algorithms
dm_cryptographic_provider_keys
dm_cryptographic_provider_properties
dm_cryptographic_provider_sessions
dm_database_encryption_keys
dm_db_mirroring_auto_page_repair
dm_db_mirroring_past_actions
dm_filestream_oob_handles
dm_filestream_oob_requests
dm_os_dispatcher_pools
dm_os_memory_brokers
dm_os_memory_nodes
dm_os_nodes
dm_os_process_memory
dm_os_spinlock_stats
dm_os_sys_memory
dm_resource_governor_configuration
dm_resource_governor_resource_pools
dm_resource_governor_workload_groups
dm_sql_referenced_entities
dm_sql_referencing_entities
dm_tran_commit_table
dm_xe_map_values
dm_xe_object_columns
dm_xe_objects
dm_xe_packages
dm_xe_session_event_actions
dm_xe_session_events
dm_xe_session_object_columns
dm_xe_session_targets
dm_xe_sessions



If you want to find out what the names of all the new DMVs are by running a query on your SQL Server 2008 box and you don't have a linked server to a SQL Server 2005 box then don't worry I have prepared the query below for you.



SELECT * FROM sysobjects
WHERE name LIKE 'dm_%'
AND name NOT IN('dm_os_hosts',
'dm_exec_cached_plan_dependent_objects',
'dm_os_memory_allocations',
'dm_os_loaded_modules',
'dm_db_task_space_usage',
'dm_os_memory_objects',
'dm_os_schedulers',
'dm_os_threads',
'dm_exec_requests',
'dm_db_missing_index_columns',
'dm_repl_tranhash',
'dm_qn_subscriptions',
'dm_db_session_space_usage',
'dm_exec_query_optimizer_info',
'dm_tran_top_version_generators',
'dm_os_waiting_tasks',
'dm_exec_background_job_queue',
'dm_exec_cursors',
'dm_db_missing_index_details',
'dm_clr_properties',
'dm_os_sublatches',
'dm_exec_query_memory_grants',
'dm_tran_current_snapshot',
'dm_io_virtual_file_stats',
'dm_exec_xml_handles',
'dm_os_wait_stats',
'dm_exec_text_query_plan',
'dm_broker_connections',
'dm_os_stacks',
'dm_os_ring_buffers',
'dm_db_missing_index_groups',
'dm_exec_cached_plans',
'dm_exec_sessions',
'dm_broker_forwarded_messages',
'dm_os_memory_clerks',
'dm_repl_articles',
'dm_fts_memory_buffers',
'dm_fts_index_population',
'dm_tran_current_transaction',
'dm_os_child_instances',
'dm_exec_connections',
'dm_exec_background_job_queue_stats',
'dm_fts_active_catalogs',
'dm_tran_database_transactions',
'dm_os_memory_cache_clock_hands',
'dm_repl_schemas',
'dm_db_mirroring_connections',
'dm_db_index_operational_stats',
'dm_db_partition_stats',
'dm_io_pending_io_requests',
'dm_os_memory_cache_entries',
'dm_os_virtual_address_dump',
'dm_tran_transactions_snapshot',
'dm_exec_query_plan',
'dm_os_memory_cache_hash_tables',
'dm_exec_query_stats',
'dm_clr_tasks',
'dm_os_worker_local_storage',
'dm_db_index_usage_stats',
'dm_db_index_physical_stats',
'dm_os_buffer_descriptors',
'dm_tran_active_snapshot_database_transactions',
'dm_tran_active_transactions',
'dm_db_file_space_usage',
'dm_broker_activated_tasks',
'dm_broker_queue_monitors',
'dm_os_memory_cache_counters',
'dm_tran_session_transactions',
'dm_clr_appdomains',
'dm_exec_sql_text',
'dm_os_memory_pools',
'dm_os_latch_stats',
'dm_io_backup_tapes',
'dm_fts_memory_pools',
'dm_os_sys_info',
'dm_tran_locks',
'dm_exec_query_transformation_stats',
'dm_exec_query_resource_semaphores',
'dm_repl_traninfo',
'dm_db_missing_index_group_stats',
'dm_fts_population_ranges',
'dm_os_performance_counters',
'dm_os_workers',
'dm_io_cluster_shared_drives',
'dm_os_tasks',
'dm_exec_plan_attributes',
'dm_tran_version_store',
'dm_os_cluster_nodes',
'dm_clr_loaded_assemblies')

Enjoy exploring these DMVs


Monday, February 04, 2008

Windows Server 2008 and Vista SP1 releasing to manufacturers today

Windows Server 2008 RTM: http://www.microsoft.com/presspass/features/2008/feb08/02-04WS2008.mspx

Windows Vista SP1: http://windowsvistablog.com/blogs/windowsvista/archive/2008/02/04/announcing-the-rtm-of-windows-vista-sp1.aspx

Should You Get Your Database Under Version Control?

CodingHorror has a blogpost titled Get Your Database Under Version Control


It is suggested that you also keep the data in version control. I am reading through the comments and I am amazed. One person writes "Once you have used ActiveRecord Migrations it is very hard to go back!"


This might work for a small or medium size database. My database is well over a terabyte, how would you keep that data under version control? Data gets modified every day. Some of the data is encrypted. Some of the data gets inserted into audit tables. Data gets replicated to other servers/databases. There are jobs that pull in data from real time systems every second. I do have different versions of DBs on staging and QA servers but only one on the production server. Changes have to go through change management, you have to open a ticket to do a change. This is not something you would do on a daily basis.


What is your opinion? Do you have the schema in version control? What about the data itself?

Friday, February 01, 2008

Vote for SQL Server 2005 Service Pack 3

Hugo Kornelis makes a good point here: Want a Service Pack? Ask for it!
Service pack 2 for SQL Server 2005 is already 11 months old. And there is still no sign of service pack 3 on the horizon. Why is that? Has Microsoft managed to release a perfect, completely bug-free product? No, of course not – with the size and complexity of a product such as SQL Server is, that will simply never happen.

So do yourself (and me) a favor and vote here: http://connect.microsoft.com/SQLServer/feedback/ViewFeedback.aspx?FeedbackID=326575

Tuesday, January 29, 2008

Some Very Sad News For The SQL Server Community

Ken Henderson passed away this last Sunday. My condolences go out to his family, friends, and coworkers. I owe so much to Ken, if it wasn't for his books I would not be where I am today.

Ken, You will be missed.

Saturday, January 26, 2008

SQL Server 2008 To RTM In Q3 2008

Francois Ajenstat on his blog writes that

"Microsoft is excited to deliver a feature complete CTP during the Heroes Happen Here launch wave and a release candidate (RC) in Q2 calendar year 2008, with final Release to manufacturing (RTM) of SQL Server 2008 expected in Q3."


You can read the whole blog post here: http://blogs.technet.com/dataplatforminsider/archive/2008/01/25/microsoft-sql-server-2008-roadmap-clarification.aspx

Friday, January 25, 2008

Tip: Find all The Rows Where Any Of The Columns Is Null Or Zero Or Both

This question is asked every now and then so I decided to do a little blog post. How can you quickly without writing a bunch of OR statements determince if any columns have a NULL value, a value of 0 or if the value is 0 or NULL.
To test for NULL is very easy, you just concatenate the columns since NULL + anything else is always NULL. Okay that also depends on a setting.

Run this

SET
CONCAT_NULL_YIELDS_NULL ON
SELECT
NULL + '1' --NULL

SET CONCAT_NULL_YIELDS_NULL OFF
SELECT
NULL + '1' --1

As you can see if CONCAT_NULL_YIELDS_NULL is OFF then the result is 1

Now take a look at this


SET CONCAT_NULL_YIELDS_NULL ON
SELECT
NULL + 1 --NULL



SET CONCAT_NULL_YIELDS_NULL OFF
SELECT
NULL + 1 --NULL


So with numeric values it behaves differently. Either way by default CONCAT_NULL_YIELDS_NULL is set to on
To test for NULLS or zeroes you use NULLIF
To test for zeros you can combine COALESCE and NULLIF

Here is the code which shows all of that

CREATE
TABLE #test(column1 int,column2 varchar(4),column3 float)

INSERT
#test VALUES(2,'2',2)
INSERT #test VALUES(0,'1',0)
INSERT #test VALUES(null,'1',0)
INSERT #test VALUES(1,null,0)
INSERT #test VALUES(0,'1',null)
INSERT #test VALUES(null,null,null)



--Any column is Null
SELECT * FROM #test
WHERE column1 + column2+column3 is null

Output
------------
NULL 1 0.0
1 NULL 0.0
0 1 NULL
NULL NULL NULL



--Any column is Null or zero
SELECT * FROM #test
WHERE NULLIF(column1,0) + NULLIF(column2,0)+NULLIF(column3,0) is null

Output
-------------------
0 1 0.0
NULL 1 0.0
1 NULL 0.0
0 1 NULL
NULL NULL NULL




--Any column is zero
SELECT * FROM #test
WHERE NULLIF(COALESCE(column1,1),0) +
NULLIF(COALESCE(column2,1),0)+
NULLIF(COALESCE(column3,1),0) is null

Output
-------------------
0 1 0.0
NULL 1 0.0
1 NULL 0.0
0 1 NULL


DROP TABLE #test

Some Links To Blogs By Some Friends Of Mine

Since I have nothing useful to post today I decided to post some links to some of my friends

The first one is from someone in Belgium, his name is Christiaan Baes and he seems to like ORM tools like NHibernate. His blog is mostly about .NET. I'll forgive the fact that he is born 100 miles south by mistake.

The second one is from Mark Smith and he blogs about ASP.NET, SQL Server, HTML, CSS and other random thoughts. Mark's other site is http://aspnetlibrary.com/

The third one is from Denny Cherry, Denny has worked with shops running hundreds of SQL Servers with over half a billion transactions per second through out the farm.

The fourth one is from Alex Cuse and I don't think Alex himself knows what he is blogging about :-)

Sunday, January 13, 2008

The last two days have been the worst of my life

The last two days have been the worst of my life; it feels like he combination of a really bad hangover, the flu and a massive toothache. It all started on Wednesday afternoon; my tooth and the gum fell a little sore. Instead of going to the dentist like a normal person I decided to wait because it will go away. Thursday it fell worse and I had to ask for Motrin at work. I did not sleep at all Thursday night, I called my dentist at 6AM but he couldn’t see me until 12:20 PM. I figured he’ll give me a shot, clean out the tooth and I’ll be back at work at 2PM.
Well it turns out a root canal I had done 10 years ago acted up and they have to do a root end resection. My dentist doesn’t do root canals; he referred me to a specialist. The specialist is fully booked and doesn’t have an opening till Tuesday morning.
My dentist prescribed Oxycodone W/APAP (also known as Oxycontin or Roxicodone) and Amoxicillin. That stuff is pretty intense, your pain goes away but you are pretty much useless. The pain is gone but now my right cheek is swollen and I have to throw up every hour or so. I just hope all this ends by Tuesday, the fix the root canal and I can be at my desk by 12PM.
The reason I wrote this is that next time I say “I have no time to floss for five5 minutes I’ll do one minute instead” I can look back at this post and hopefully change my mind