Be Aware of These Loopholes in Your Referential Integrity
I am going to discuss several potential problems with referential integrity, because they keep coming up in the newsgroups.
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Log Shipping with Security
Many DBA's struggle with maintaining their security infrastructure while providing the ability for dev to access the delivery environment. A common approach is to setup a NRT (Near Real Time) environment on a warm server. There are several approaches to this. If you're looking just to push data SSIS or replication seems to fit the needs. The problem with these approaches is that it's not a true representation of delivery. Since you're only shipping data it often leaves out schema items such as stored sprocs and views that might have changed in the last release.
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Performance Effects on Column Type Changes
The other day I was given a request to change a field from varchar(6) to varchar(10). Not thinking it was a big deal I said just give me the checked in code and I'll make the change. One of our sharper dev's (Bill Carlson) was concerned with the lock caused by this statement. I'd never actually took a deep dive on how this would occur so I decided to run a quick test to see what would happen. Making this change on a 2.5 million row table took 10 ms.
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Security and Encryption for SQL Server Compact
The nice thing about SQL Server Compact is the database can be treated as a document. It's a single file, it's only "open" when being used and can use the standard set of security mechanisms that any other document can. You can set ACLs on the files, and you can encrypt the file with the Windows Encrypted File System.
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There's a bright cloud on the horizon ... and it will transform the economics of BI
Cloud computing is ushering in a new era of analytic data management for business intelligence (BI) by enabling organizations to analyze terabytes of data faster and more economically than ever before. The key change: It's delivered in an on-demand basis.
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Why SSIS over DTS?
Running DTS in SQL 05 (using SSIS) only provides a “wrapper” to the DTS package.The package will not take advantage of the performance gains that SSIS has to offer.· Clients that are using DTS to move data into a data warehouse will inevitably experience
larger and larger volumes of data to move, clean, and transform.
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How hard is it to pick the right non-clustered indexes?
Kimberly and I were presenting at our local (Redmond) .Net Developers Association on Monday and the following question came up while Kimberly was talking about missing and extra indexes (paraphrasing):
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Internet Explorer "Print Table of Links" Cross-Zone Scripting
Input passed via links within an HTML file is not being properly sanitised before being used to generate a printable HTML file. This can be exploited to inject arbitrary script code, which is executed in local context when a user is enticed to print a specially crafted HTML document with the "Print table of links" option enabled.
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SQL Server 2008 Page Compression: Performance impact on inserts
Before I begin, let me be very clear that the results I report in this post were obtained with SQL Server 2008 CTP6. Microsoft is still working on improving the performance of data compression. And in particular, the performance of inserting into a compressed table is expected to be significantly enhanced in SQL Server 2008 RTM.
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Contradictions within Contradictions
I had a question from a reader about contradiction detection. The basic idea is to determine that this kind of query: SELECT * FROM TABLE WHERE col1 > 5 and col1 < 0;
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Internet Explorer "DisableCachingOfSSLPages" Weakness
Internet Explorer supports the "DisableCachingOfSSLPages" option, which is supposed to prevent encrypted web pages from being saved to disk. However, an error may result in encrypted web pages being cached regardless of the setting being enabled or not.
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Microsoft Word Two Code Execution Vulnerabilities
Two vulnerabilities have been reported in Microsoft Word, which can be exploited by malicious people to compromise a user's system.
1) An error when parsing objects in rich text format (.rtf) files can be exploited to corrupt memory e.g. when a user opens a specially crafted .rtf file containing malformed strings with Word or previews a specially crafted e-mail containing malformed strings as rich text or HTML.
2) An error exists in the processing of cascading style sheets (CSS) values and can be exploited to corrupt memory when a specially crafted Word file is opened.
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Microsoft Malware Protection Engine File Parsing Denial of Service
Two vulnerabilities have been reported in various Microsoft products, which can be exploited by malicious people to cause a DoS (Denial of Service).
1) An unspecified error in the Malware Protection Engine when parsing files can be exploited to cause the engine to stop responding and restart when scanning a specially crafted file.
2) An unspecified error in the Malware Protection Engine when parsing files can be exploited to exhaust available disk space when scanning a specially crafted file.
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The identity column of the destination table does not contain the same identity values as the source table
Consider the following scenario:
• In Microsoft SQL Server 2005, you use SQL Server Management Studio to import data or to export data from a source table to a destination table.
• Both the source table and the destination table include an identity column.
• You enable the Enable identity insert option for the source table.
• In the SQL Server Import and Export Wizard, you enable the Optimize for many tables option.
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A query that references a nondeterministic user-defined function may run slower in SQL Server 2005
In Microsoft SQL Server 2005, a query that references a nondeterministic user-defined function may run slower than the same query runs in SQL Server 2000.
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FIX: Error message when you create a subscription in SQL Server 2005 Compact Edition
You have a table in Microsoft SQL Server 2000 that contains a clustered index and a nonclustered index. You specify the FILLFACTOR option on the clustered index, and then you create a merge publication on the table. When you try to create a subscription in Microsoft SQL Server 2005 Compact Edition, you receive the following error message:
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Common Table Expressions (CTE's) - How it works; How Recursion Works; Using with Adjacency List
Recursion in Common Table Expressions (CTE’s), how does it work? How can I use it with the agancy list model (parent / child columns)? In this blog entry I show how recursion works, how to use it with the agency list model and talk about other aspects
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SQL Server 2008 Page Compression: Compression ratios with real-world databases
In my previous post on data compression, I looked at how rebuilding a table with page compression works with multiple processors via the MAXDOP option. In this post, I'll focus on what compression ratios I have seen in the real-world databases. Now, if you understand how SQL Server 2008 data compression works, you know that what compression ratio you may get really depends on to what extent SQL Server can find duplicate values on the data/index pages.
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Dynamic ordering with T-SQL
This is an oldie, but a goodie. I was talking to Dave Gardiner about a question he had recently, the question of how to dynamically sort the results of a T-SQL query.
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Vertica moves BI database to Amazon's EC2 cloud
Database maker Vertica Systems is moving its technology to Amazon's Elastic Compute Cloud infrastructure (EC2), hoping to score customers who want a hosted, pay-as-you-go model for data warehousing and BI (business intelligence), the company announced Monday.
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24 Hours of SQL Server 2008: Data Mining
Wednesday, May 21, 2008
11:30 AM Pacific Time
Contoso wants to implement data mining to help the sales department better understand its customer base and forecast future sales based on historical trends. In this webcast, we review the data mining capabilities of the Microsoft business intelligence (BI) platform
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24 Hours of SQL Server 2008: AS Design and Performance Improvements
Monday, May 19, 2008
11:30 AM Pacific Time
This webcast was designed for IT professionals and developers. To support high-performing ad hoc analysis, Contoso wants to develop a Microsoft SQL Server Analysis Services database. In this webcast, we review the new features in Analysis Services that may help Contoso accelerate development and achieve optimal performance.
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Garden State Goes for Green IT
New Jersey IT managers are going green to save green, but they want to see fast ROIs
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A query that references a nondeterministic user-defined function may run slower
In Microsoft SQL Server 2005, a query that references a nondeterministic user-defined function may run slower than the same query runs in SQL Server 2000.
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