Tag: SQLServer 2012

SQL Server Feature Limitations (Windows Azure SQL Database)

I’ve just received a question about features comparison between SQL Server and SQL Azure Database. This is one of the most frequently asked questions I receive in my blog PMs and forums.. Thus, I’m sharing the links in order to gather some information about this topic.

and
Another good start can be this link.
Stay Tuned! 🙂

ALTER SCHEMA does not reflect changes into the sys.sql_modules catalog view (definition)

I have recently found a strange behavior related to a comfortable DDL command, the ALTER SCHEMA statement. That happened while I was trying to move a stored procedure from a schema to another one. Both stored procedure and function definitions are stored on a catalog object which is accessible by the sys.sql_modules catalog view (column “definition”). After executing the ALTER SCHEMA statement the definition field is not updated.

We’re speaking about both SQL Server 2012 on premise and SQL Azure databases. My current SQL Server 2012 version/edition is:

Microsoft SQL Server 2012 (SP1) – 11.0.3128.0 (X64) 
Dec 28 2012 20:23:12 
Copyright (c) Microsoft Corporation
Developer Edition (64-bit) on Windows NT 6.2 <X64> (Build 9200: ) (Hypervisor)

Continue reading “ALTER SCHEMA does not reflect changes into the sys.sql_modules catalog view (definition)” →

Differences between SSMS and ado.net: query execution time

Sometimes, in the forums I’m following, I face some questions about different execution times between Sql Server Management Studio and ado.net executions.

Questions like “Why my SSMS queries run so fast and my ado.net queries are so slow?”. This is a scaring behavior that you can verify lots of times. Some application’s logs tell to us a too large timing. When you copy/paste the SQLCommand into a new query window using SSMS (also on the incriminated server) the execution time is very short.

Continue reading “Differences between SSMS and ado.net: query execution time” →

SQL Server Logical Query Processing summary

Usually I found some questions on the forums about that topic. For instance:

  1. “WHERE or HAVING?”
  2. “Is the ON clause more efficient than the WHERE clause?”
  3. “Why the field aliases cannot be used with the GROUP BY clause?”
These three questions are syntax oriented. Actually there are a lot of requests about subqueries, temporary objects, sort operations and so on. This kind of questions can be replied reading this logical process document (pdf). I love it and I share it everywhere, also when training in classes/on the job.
It is a LOGICAL workflow used by the Query Processor in order to generate the related PHYSICAL process for retrieving data.