A SQL statement typically used to `UPDATE` records when they exist and `INSERT` them when they do not.

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How to use merge hints to isolate complex queries in SQL Server

I can understand that if I join individual queries that are "individually fast" the combination may become slow because the default execution plan may be non-optimal. However when I know the number ...
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What are my locking options for a Merge statement?

I have a stored procedure that performs a MERGE statement. It seems like it locks the whole table by default when performing the merge. I'm calling this stored procedure inside of a transaction ...
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What overhead is there if I MERGE row by row?

I have a target table of about 2000 rows and I want to be able to MERGE (with HOLDLOCK) about 5-10 rows at a time into the target table. The target table doesn't get used heavily, with only 1-2 users ...
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Re-subscribing to a merge publication after edits made offline

Hypothetical Question - To help scenario planning. Let's say I have a 2008 R2 Merge Publication with 5 active subscribers. The publication is deleted and all subscriptions are removed. A week or so ...
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Oracle's Merge v. Select->Update/Insert

What is the faster statement? A MERGE or Select->Update/Insert depending on if it returns a value? I'm trying to optimize a database, but I haven't found any speed tests comparing the two. I found ...