使用 MS Access 更新 SQL Server 视图上的查询超时

Question

I am having some trouble with updates to an SQL Server View through MS Access. The set of tables used for this is built off of a base table. This base table is of this format.

Id    int (not-nullable; auto-assigned)
A1    varchar(50) (nullable)
A2    varchar(50) (nullable)
B1    varchar(50) (nullable)
B2    varchar(50) (nullable)
C1    varchar(50) (nullable)
C2    varchar(50) (nullable)

One row on this table is updated by multiple groups of users in our company. For instance, user group "A" updates columns "A1" and "A2", user group "B" updates columns "B1" and "B2", and so forth. However, we also want to prevent user group "A" from updating the columns of user group "B". To accomplish this, I set up a view containing the columns appropriate for each user group. For instance, the view for user group "A" would only contain the columns "Id", "A1", and "A2". Then I set the "Bind To Schema" option on the views in SSMS to "Yes", and I set up a unique, clustered index on the "Id" column on each of the views. In MS Access, I connect to these views as linked tables using an ODBC connection. When I open the tables in MS Access in design view and check the indexes, it does properly identify the "Id" column as the primary key.

Here is where the trouble comes in: When I try to update a record through MS Access in one of the views, sometimes the update runs instantly, but sometimes the update times out. Here is the error that I get.

"SM_Notes_Bridge" is the actual name of one of my views. Almost all previous answers that I can find online say to increase the amount of time before the update times out in MS Access, which seems like it is not a solution for my problem as the update either runs instantly or times out. There is no middle ground.

Another note is that I am currently the only one using this base table and these views. Also, important systems are developed around that base table structure, so changing its structure will take a lot of convincing.

Answer 1

By creating an unique index on a schema bound view, you're creating an indexed view, also called a materialized view .

A relevant property of indexed views:

When executing DML on a table referenced by a large number of indexed views, or fewer but very complex indexed views, those referenced indexed views will have to be updated as well. As a result, DML query performance can degrade significantly, or in some cases, a query plan cannot even be produced ( MSDN ).

Thus, creating multiple indexed views on a table that is updated often is a big no-no! Review this MSDN page for further explanation when and when not to use an indexed view. Every insert and update will have to propagate to all the indexed views, and will cause locks on those views as well.

Drop the indexes on ALL views on that table. As far as you've told me, there's no reason at all to use indexed views and they will hurt performance in a major way when executing updates. Even if that didn't fix this issue, it will improve performance.