SQL Best Practices Analyzer Rule: Use of Schema Qualified Tables/Views

SQL BPA says the following:

"One or more objects are referencing tables/views without
specifying a schema! Performance and predictability of the
application may be improved by specifying schema names."

"When SQL Server looks up a table/view without a schema
qualification, it first searches the default schema and then the
'dbo' schema. The default schema corresponds to the current
user for ad-hoc batches, and corresponds to the schema of a
stored procedure when inside one. In either case, SQL Server
incurs an additional runtime cost to verify schema binding of
unqualified objects. Applications are more maintainable and
may observe a slight performance improvement if object
references are schema qualified."

How important is to specify the schame (dbo. in my case) in
stored procedures? Will it really improve performance if I go
and fix each object that is missing "dbo."?

The problem is I have thousands and thousands of them
with no schemas. Before I invest a lot of time fixing them
I am trying to determine if it's really worth it or not?

Thank you

> How important is to specify the schame (dbo. in my case) in
> stored procedures? Will it really improve performance if I go
> and fix each object that is missing "dbo."?

It will improve performance but the 'slight performance improvement'
probably doesn't justify a significant effort to implement the
recommendation for thousands of instances.  However, you should
schema-qualify objects for new development and perhaps as you perform
maintenance.

--
Hope this helps.

Dan Guzman
SQL Server MVP

"serge" <sergea@nospam.ehmail.com> wrote in message
news:gOrof.14720$yf7.259350@weber.videotron.net...
> SQL BPA says the following:
>
> "One or more objects are referencing tables/views without
> specifying a schema! Performance and predictability of the
> application may be improved by specifying schema names."
>
> "When SQL Server looks up a table/view without a schema
> qualification, it first searches the default schema and then the
> 'dbo' schema. The default schema corresponds to the current
> user for ad-hoc batches, and corresponds to the schema of a
> stored procedure when inside one. In either case, SQL Server
> incurs an additional runtime cost to verify schema binding of
> unqualified objects. Applications are more maintainable and
> may observe a slight performance improvement if object
> references are schema qualified."
>
> How important is to specify the schame (dbo. in my case) in
> stored procedures? Will it really improve performance if I go
> and fix each object that is missing "dbo."?
>
> The problem is I have thousands and thousands of them
> with no schemas. Before I invest a lot of time fixing them
> I am trying to determine if it's really worth it or not?
>
> Thank you
>
>