At first we wrote reports just "straight up", without any locking hints in the queries. With the larger reports this would sometimes cause locking problems. At first we remedied this by using the
WITH (NOLOCK) hint for tables in the query.
Because (a) it's quite obtrusive, and (b) it's easy to forget the hint for one of the tables, we moved to a second approach setting
TRANSACTION ISOLATION LEVEL to
READ UNCOMMITTED (which is fine) at the top of each dataset's query.
As you may guess, it's still easy to forget the hint for one of the datasets. So this leads to the question:
Question: What are the options for sending
NOLOCK hints along with report queries?
PS. I realize this is to some extent an XY-problem (with a lot of my other options for X, such as optimizing the query, not doing reporting on the operational database, etc), but tried to make this a valid question on itself nonetheless.
Here are the options mentioned above, with added options about which I'm curious if they would work:
WITH (NOLOCK)hint for each table. (obtrusive, very easy to forget)
- Set isolation level to
READ UNCOMMITTEDfor the entire query. (still easy to forget)
- Is it possible to specify this at the report level? E.g. make sure all dataset queries for one report will be run without locking.
- Is it possible to specify this at some other SSRS level? E.g. perhaps set this for a certain Report Folder, or by utilizing an extension?
- Is it possible to specify this at the data source / connection string level? E.g. have all relevant reports use a certain "No-lock-data-source"?
- Related to the previous option: perhaps it's possible to specify a default locking hint for a specific "no-lock-sql-user" (the one that's used in the connection)?
Which options are viable? Are there options I've missed?