Ntext vs Nvarchar(Max)

	Ntext	Nvarchar(max)
Default Behavior	Data is stored as a LOB	Stores data in-row
Data is stored	Out of the data page as LOB	Stored data In-Row ( if less than 4000) Stored as LOB ( when more than 4000)
Read-aHead Reads	All the rows are read-ahead every time. Does not seems to depend on the cache	Didn’t read-ahead during the testing
Elapse time to insert 200 records Ex insert into testTable1 select REPLICATE('ABBD455',2000) go 200	High	Low

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Create a dacpac To Compare Schema Differences

It's been some time since i added anything to the blog and a lot has happened in the last few months. I have run into many number of challenging stuff at Xero and spread my self to learn new things. As a start i want to share a situation where I used a dacpac to compare the differences of a database schema's. - This involves of creating the two dacpacs for the different databases - Comparing the two dacpacs and generating a report to know the exact differences - Generate a script that would have all the changes How to generate a dacbpac The easiest way to create a dacpac for a database is through management studio ( right click on the databae --> task --> Extract data-tier-application). This will work under most cases but will error out when the database has difffrent settings. ie. if CDC is enabled To work around this blocker, you need to use command line to send the extra parameters. Bellow is the command used to generate the dacpac. "%ProgramFiles...

High Watermarks For Incremental Models in dbt

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The maximum number of working threads (100) are already running

The problem This afternoon, out of the blue, the development folks called over wanting to know why the DB server was not responding, sure enough the databases were not accessible from application and from MMS. I knew there weren’t any maintenance happening and so I logged in to the server remotely and found that the sql services were still running as usual and the services had not restarted. To my surprise, in 10-15 mins everyone was able connect to the server again. My first thoughts were, it would have been an issue with the network and due to the glitch the servers weren’t accessible during the time period. Environment details : - The sql server were on a hyper v with a single CPU and 1024 memory - There was 80 + transaction replications setup and further 20-30 sql ser...

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