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writing to tempdb is faster than an actual table not in tempdb It's true. There are two IO enhancements in TempDb. Writes to a table in a user database must have their log records flushed to …

What’s a good use of select * in production? IMO only things like this: eg create table #foo(a int, b int, c int, d int) ... select * from #foo or with q as ( select a, b, c from ... ) …

If you have a small-enough number of (StationID, ParameterID) pairs, then try a query like this: select StationID, ParameterID, m.DateTime LastDate from StationParameter sp cross apply ( sel …

They are different strings. select cast(N'pskalhaq' as varbinary(200)) union all select cast(N'‏pskalhaq' as varbinary(200)) outputs 0x700073006B0061006C00680061007100 0x0F20700073006B0061006C0 …

If I have a table where the data is guaranteed to never change, is it completely safe to add the NOLOCK hint to my SELECT queries against that table? In practice, yes (although not documented as suc …

Concurrent MERGE statements will deadlock or produce PK violations by default, as the "scan" phase of the MERGE is performed without a restrictive lock. You need to add a lock hint for this to work. …

How will SQL Server queue this request (eg First In First Out)? Can I be sure the DROP COLUMN will truly only take a few moments? The way the locking works for ALTER TABLE is that you need a Sc …

Yes. OPTION RECOMPILE is appropriate for high-cost/low-frequency queries where the query cost varies significantly by parameter values. As an alternative consider using the Query Store, where you ca …

Your parameters have a lower Data Type Precedence than the columns they are compared to. In this case the parameter values will be implicitly converted. This is a good thing. Converting the column …

A table scan on cascade delete is a common symptom of not having proper indexes on your tables. Ensure that all of the FK tables have indexes supporting the foreign keys. IE a clustered or non-clust …

Door Number 1, 2, or 3: 2, with a dash of 3. An ownership chain should prevent permission checks on a scalar UDF referenced from a view, so a user with SELECT permission on the view should not also …

There's an XEvent for that: query_cache_removal_statistics Occurs when a query plan is removed from the plan cache and the historical statistics for the object are about to be destroyed S …

Using three-part names in queries that reference objects in the current database is a terrible practice and you should create a rule against it. The most frequent problem with it is that it prevents …

The declared size of the varchar rarely has a performance impact1. The data might be actually stored as a rowstore with page compression or row compression. As a Clustered Columnstore, or as a Memor …

what would be my storage account? MYCOMPANYbackups How can I have access to the backup files? http://portal.azure.com or AzCopy or PowerShell or Azure Storage Explorer Where are these …