However when I try to execute a stored procedure in Linked Server, it throws: Deferred prepare could not be completed. Nevertheless, to simplify this text, I assume that all issues found by strict checks are reported as errors and I don't discuss the possibility of reporting them as mere warnings any further. Thus, an idea here would be keep the current behaviour when strict checks are on, but change the behaviour when strict checks are off. I guess they did not make the same change for variables for compatibility reasons. That is, the two INSERT statements above would both be legal, but this would be illegal: INSERT tbl (a, b, c, d) SELECT a, b AS myownalias, 1 AS c, coalesce(d, 0) FROM src. Appears: CREATE PROCEDURE inner_sp AS INSERT #tmp /* NOSTRICT */ (... ) SELECT...
A common cause of this error is when you try to run OPENQUERY () against the local server. So I can understand why Microsoft dropped this rule in SQL 7. There are 3 different types of database connections (that can be created using Controller Configuration's database conversion utility): - Controller DB. Here the programmer has computed the turnover for a product in a temp table, and returns the data together with som data about the product and the product category in a query. In this marvellously consistent language known as Transact-SQL, the default here is varchar(30), not varchar(1). But that could be a bit too strict even for me in some situations. But if you run it, you will get a slew of error messages: Msg 4104, Level 16, State 1, Procedure some_sp, Line 4. We saw above that the errors we got above was due to a query that referred to a temp table that was defined within the procedure. Not an uncommon mistake. Customer].. error as yours: Il provider OLE DB "SQLNCLI10" per il server collegato "RIBOWEB10\SQLEXPRESS" ha restituito il messaggio "Deferred prepare could not be completed. Admittedly, it would be best to be without a general loophole to keep the language clean.
NOSTRICT */ in this document. The reader may object that strict checks is no full guarantee that code will not blow up at run-time because of missing tables, since a table could be dropped after the procedure has been created. In my case I was searching for. And moreover, once you see that one column has an alias, you can inspect the SELECT query, and do not really have to consider the INSERT list and look for matching errors. But if the procedure creates a static table, it should be handled in the same way. Consider: SELECT cast(intcol AS varchar). The statement has been terminated. If Microsoft makes this a pure run-time check, there is also no reason that the file could not be specified through a variable, but that's another story. Since this is loss of information, this should yield an error when strict checks are on.
And then it bombs when you run it. The table variable scope is within the batch. As an index may be added in the future. XML, sql_variant and CLR types to String are not listed since there are no such implicit conversions today. With errors, SQL Server reports a line number, and this line number is displayed in the query tool, and the programmer can double-click on the line to quickly find the error. It hasn't happnened yet, but the optimist in me never gives up! The user types are not compatible: user types must be identical in order to join. It's a decent workaround for some, but in the long run, this should be in the engine. We can enable this trace flag at the global level using DBCC TRACEON(2453, -1) command as well: 16. Just like bulk-copy objects, this is a situation where I may prefer to not be alarmed about something missing, or at least not missing servers, at compile time. On SQL 7 and later, this procedure is created without an error, and then bombs at run-time because of the missing column. It allows SQL table variable recompilation when the number of rows changes. Solution of this error is really pretty much simple. For instance, this procedure creates and executes without an error on SQL 6.
What is a little more realistic is that only some of the issues found by strict checks are reported as errors, whereas others are reported as warnings. You could argue that it may be a typo, and therefore the programmer is helped by being informed about the error. By the way, things are not any better with OPENQUERY: CREATE PROCEDURE linkaccess2 AS SELECT * FROM OPENQUERY(SERVER1, 'SELECT OrderID FROM '). Option Explicit and Perl has.
I can sympathise with the idea, but I will have to admit that I much prefer the version to the left in the queries below: SELECT OrderID, CustomerID, OrderDate SELECT O. OrderID, stomerID, O. OrderDate FROM Orders FROM Orders O WHERE EmployeeID = 19 WHERE O. EmployeeID = 19. Let's look at some examples. SQL Server missed the estimation of actual rows counts by 1997200% for the execution plan. Note that there should be an error, regardless whether the column is indexed or not. The net effect is that the optimizer often estimates them to have one row, which can lead to disastrous plan choices. But recall what I said: deferred name resolution was introduced in SQL 7. And that is alright, as long as line numbers are reported for these warnings. The fourth is a breach against the basic idea, as only one table is included in the condition. Use the CONVERT function to run this query, but rather encourage the programmer to avoid the type clash altogether. Row mode memory grant feedback. Use MyDatabase -- Use this to get instance login sid. 5 could do it, why not later versions? I will now leave the area about temp tables and cover some other situations where deferred name resolution raises its ugly head. However, table variable are notorious for being performance busters.
Obvious things like. One alternative would be to have BEGIN NOSTRICT and END NOSTRICT and within this block strict checks would be turned off. With strict checks in force, the compilation would fail directly and the behaviour would be cleaner. SSDT understands to extract temp-table definitions and will give you an warning if you refer to a temp table that it does not know about, or if you misspell a column in a temp table. If we look at the statistics in SQL Server 2019, we can see it took 43, 783 logical reads in comparison with 59, 992 logical reads in SQL 2017. I chose REFERENCES in the second case, since that is already a reserved keyword, and it sort of fits.
The reader may think that OR terms should be handled similarly to AND factors, but OR is so much less common, that I don't think it's worth making any. From all versions from SQL 7 and on, this passes. Essentially, it opens a linked server, then executes a query as if executing from that server. We can start with the observation that queries like this one are difficult to read for the outsider who don't know the tables. Nevertheless, if you have further suggestions, please feel free to drop me a line at If I agree with you, I may add the suggestion to the article.