Waiting for locks is normal in SQL Server (or any other relational db).

Whether the waits are excessive is a different q.

Since you've provided no details, to reduce bad effects...

Locks are a required part of SQL Server.  You wouldn't want 2 queries updating a single piece of data at the exact same time.  Much better for them to...

Thank you Adi Cohn for your kind help!

It will show you details only on plans that exist in the query cache.  As soon as a query plan is being deleted from the query plan, you won't...

Ah, but it appears that may be operating under a really bad premise.  Changing a VARCHAR(200) to a VARCHAR(100) will, by itself, DO NOTHING to save on space.  The...

Thank you but the question above is...

Thank you but the question above is basically just...

we can use sp_spaceused to know how many space reservred by a table and know how many spaces for data space and index space, but if there is...

Thank you Anthony.green!

Jeff  Moden, thank you for your help and guidance !

Yes, I know sql...

In the main table storage area, a row will be on one and only one page.  Any other data for that row must go to overflow pages.

-1- There's not...

Slight bit of misunderstanding there. Let's say we have a VARCHAR(50). Now let's say that our data stored there is 'dog'. It doesn't use storage out to 50 characters....

For most of us, most of the time, that's way too much detail. It begs the question, what problem are you really trying to solve.

However, if you want crazy...

Additionally understanding that the WHERE clauses and JOIN criteria (if any) for data manipulation queries are subject to all the same rules as a SELECT query. Something like a...