Can somebody else please provide feedback and let me know if this is happening to them too? This could be a problem with my internet browser because I've had this happen before. You definitely know what youre talking about, why waste your intelligence on just posting videos to your site when you could be giving us something enlightening to read? 14
This way we can get the original table back if aggregate functions was not applied on the data or data was in such form that aggregate function might have not made any difference. Fill in your details below or click an icon to log in: Email (required) (Address never made public) Name (required) Website You are commenting using your WordPress.com account
SQL Server Forums - Article: Calculating Running Totals
Within queries, this can be achieved by having one query return the first record, and if the record being executed is the first record, then it resets the stored value. This compares to about 7 seconds with the correlated subquery.As an aside, does anyone know if SQL Server will be adding analytic functions like Oracle has? This is a much better solution to this problem (performance wise)
Conclusion Using simplified CASE expression statements results to have cleaner code and speed up development time, but they show poor performance in some situations. Dynamic SQL Using above four solutions we could not achieve good performance, because we need different efficient execution plan for each combination of input parameters
Sometimes a single query with 20 joins will perform just fine, and a query with 4 joins will actually perform better if split into steps that fill temp tables that are then joined. When you write new code, instead of using SELECT INTO, if you use a CREATE TABLE followed by INSERT SELECT, your code will be cloud-ready in this respect
Function Categories Functions can be divided into three distinct categories: Equivalent Functions: Those that can be safely migrated from one database type to another without any modifications whatsoever. Emulated Functions Functions that have no equivalent on the other platform are where the bulk of your efforts will go, as converting these can be like trying to fit a round peg into a square hole
Dotnet Difference FAQs Blog
http://onlydifferencefaqs.blogspot.com/6 How to describe WCF services ? WCF SOAP services can be described in WSDL allowing automated tools to generate client proxies even for services with complex schemas. 10 When to go for WCF ? Choose WCF when we want to create a service that should support special scenarios such as one way messaging, message queues, duplex communication etc
Then check if the error is in the app code itself, or it this message is the result of catching a different error, and in the latter case find out what the original error was. Also, blogs are not really a good place for posting these questions; I suggest that you post your future questions to one of the many available online support forums on Internet
first i inserted 500.000 rows into a table with 5 columns: create table TestTable (col1 varchar(50), col2 varchar(50), col3 varchar(50), col4 varchar(50), col5 varchar(50)) in which for each 100k rows one column was filled with 50 chars and the rest were null. I'm not sure why that is, but I'm assuming it's a bug with STATISTICS TIME rather than an indication of performance, considering that the runtimes were identical
Views vs Stored Procedures, whats the difference? - Microsoft SQL Server
What is the purpose of a view if I can just copy the vode from a view and put it into a stored procedure? The purpose of view is that it can be used within a query. Unlike your often ambiguous ranting I've just backed my statement up - go get Ken's book, or go and read some of the many white papers on SQL Server internals
Querying SQL Server 2012: Part II - CodeProject
8.1 CROSS APPLY The CROSS APPLY operator works like an INNER JOIN in that it can match rows from two tables and leaves out rows that were not matched by the other table in the result. The following query gets the top three most expensive orders regardless of customer and as a result each Person is duplicated three times in the result (once for each order, regardless of whether the order was placed by this Person)
Adam Machanic : Performance: ISNULL vs. COALESCE
I ran these tests several times on a few different servers, and ISNULL appears to pretty consistently out-perform COALESCE by an average of 10 or 12 percent. He is a Microsoft Most Valuable Professional (MVP) for SQL Server, a Microsoft Certified IT Professional (MCITP), and an alumnus of the INETA North American Speakers Bureau
Therefore, the CASE expression looks like this: CASE WHEN NULL IS NOT NULL THEN NULL ELSE 0 END Try again, but this time using ISNULL instead of COALESCE: SELECT ISNULL( (SELECT SUM(col1) FROM dbo.T1), 0 ); This time you get the output 42. Can you explain how this could happen? In order to explain what happened, you need to examine the execution plan for the query in connection 2 shown in Figure 2
The ISNULL() function looks at the first value and the second parameter value is automatically limited to that length but COALESCE() does not have this restriction. Example declare @test varchar(3) select isnull(@test, 'ABCD') AS ISNULLResult select coalesce(@test, 'ABCD') AS coalesceResult OUTPUT In the above image, the test variable has length 3
sql server - SQL - Difference between COALESCE and ISNULL? - Stack Overflow
USE tempdb; GO -- This statement fails because the PRIMARY KEY cannot accept NULL values -- and the nullability of the COALESCE expression for col2 -- evaluates to NULL. This makes a difference if you are using these expressions in computed columns, creating key constraints or making the return value of a scalar UDF deterministic so that it can be indexed as shown in the following example
This makes a difference if you are using these expressions in computed columns and creating key constraints or making return value of a scalar UDF deterministic so that it can be indexed
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