BACKGROUND:
I know how to run query against all databases on an instance, but I find that it returns correct results for some of the databases and incorrect ones for the other databases. All my databases have identical schema so there is no reason for the query to work agains some databases correctly and produce fake results for other databases. Basicaly query should show if record XYZ exists in Users table. If record exists query should return relevant record. Otherwise it should print NULL.
This is my query:
CREATE TABLE ##tempUsers(DB_Name VARCHAR(MAX), userID VARCHAR(MAX), role VARCHAR(MAX));
GO
DECLARE #command varchar(1000)
SELECT #command = 'Use ? INSERT INTO ##tempUsers select ''?'', userID, role from users where userID = ''XYZ'';'
EXEC sp_MSforeachdb #command
GO
SELECT Name, UserID, Role
FROM ##tempUsers i RIGHT JOIN sys.databases o
ON o.name = i.db_name
GO
DROP TABLE ##tempUsers;
PROBLEM:
Query correctly identifies some of the databases containing given record in given table. There are also some databases that query shows as NULL even though they have the record that is needed. For such databases NULL is returned even though they contain record in question. Schema is identical across all databases and the databases are not case sensitive.
Through elimination I was able to find that the following part of the query is only inserting results from some databases to the temporary table.
SELECT #command = 'Use ? INSERT INTO ##tempUsers select ''?'', userID, role from users where userID like ''%tempUsers%'';'
EXEC sp_MSforeachdb #command
WHAT I TRIED
1) Running simple SELECT column1, Column2 against each of the databases that was mistakingly identified as not containing record produces correct results.
2) I tried to replace = '' with LIKE %%, but it made no difference.
QUESTION:
How can I alter my query so that it returns corrent results for all databases and not just for some of them?
Related
It looks like #temptables created using dynamic SQL via the EXECUTE string method have a different scope and can't be referenced by "fixed" SQLs in the same stored procedure.
However, I can reference a temp table created by a dynamic SQL statement in a subsequence dynamic SQL but it seems that a stored procedure does not return a query result to a calling client unless the SQL is fixed.
A simple 2 table scenario:
I have 2 tables. Let's call them Orders and Items. Order has a Primary key of OrderId and Items has a Primary Key of ItemId. Items.OrderId is the foreign key to identify the parent Order. An Order can have 1 to n Items.
I want to be able to provide a very flexible "query builder" type interface to the user to allow the user to select what Items he want to see. The filter criteria can be based on fields from the Items table and/or from the parent Order table. If an Item meets the filter condition including and condition on the parent Order if one exists, the Item should be return in the query as well as the parent Order.
Usually, I suppose, most people would construct a join between the Item table and the parent Order tables. I would like to perform 2 separate queries instead. One to return all of the qualifying Items and the other to return all of the distinct parent Orders. The reason is two fold and you may or may not agree.
The first reason is that I need to query all of the columns in the parent Order table and if I did a single query to join the Orders table to the Items table, I would be repoeating the Order information multiple times. Since there are typically a large number of items per Order, I'd like to avoid this because it would result in much more data being transfered to a fat client. Instead, as mentioned, I would like to return the two tables individually in a dataset and use the two tables within to populate a custom Order and child Items client objects. (I don't know enough about LINQ or Entity Framework yet. I build my objects by hand). The second reason I would like to return two tables instead of one is because I already have another procedure that returns all of the Items for a given OrderId along with the parent Order and I would like to use the same 2-table approach so that I could reuse the client code to populate my custom Order and Client objects from the 2 datatables returned.
What I was hoping to do was this:
Construct a dynamic SQL string on the Client which joins the orders table to the Items table and filters appropriate on each table as specified by the custom filter created on the Winform fat-client app. The SQL build on the client would have looked something like this:
TempSQL = "
INSERT INTO #ItemsToQuery
OrderId, ItemsId
FROM
Orders, Items
WHERE
Orders.OrderID = Items.OrderId AND
/* Some unpredictable Order filters go here */
AND
/* Some unpredictable Items filters go here */
"
Then, I would call a stored procedure,
CREATE PROCEDURE GetItemsAndOrders(#tempSql as text)
Execute (#tempSQL) --to create the #ItemsToQuery table
SELECT * FROM Items WHERE Items.ItemId IN (SELECT ItemId FROM #ItemsToQuery)
SELECT * FROM Orders WHERE Orders.OrderId IN (SELECT DISTINCT OrderId FROM #ItemsToQuery)
The problem with this approach is that #ItemsToQuery table, since it was created by dynamic SQL, is inaccessible from the following 2 static SQLs and if I change the static SQLs to dynamic, no results are passed back to the fat client.
3 around come to mind but I'm look for a better one:
1) The first SQL could be performed by executing the dynamically constructed SQL from the client. The results could then be passed as a table to a modified version of the above stored procedure. I am familiar with passing table data as XML. If I did this, the stored proc could then insert the data into a temporary table using a static SQL that, because it was created by dynamic SQL, could then be queried without issue. (I could also investigate into passing the new Table type param instead of XML.) However, I would like to avoid passing up potentially large lists to a stored procedure.
2) I could perform all the queries from the client.
The first would be something like this:
SELECT Items.* FROM Orders, Items WHERE Order.OrderId = Items.OrderId AND (dynamic filter)
SELECT Orders.* FROM Orders, Items WHERE Order.OrderId = Items.OrderId AND (dynamic filter)
This still provides me with the ability to reuse my client sided object-population code because the Orders and Items continue to be returned in two different tables.
I have a feeling to, that I might have some options using a Table data type within my stored proc, but that is also new to me and I would appreciate a little bit of spoon feeding on that one.
If you even scanned this far in what I wrote, I am surprised, but if so, I woul dappreciate any of your thoughts on how to accomplish this best.
You first need to create your table first then it will be available in the dynamic SQL.
This works:
CREATE TABLE #temp3 (id INT)
EXEC ('insert #temp3 values(1)')
SELECT *
FROM #temp3
This will not work:
EXEC (
'create table #temp2 (id int)
insert #temp2 values(1)'
)
SELECT *
FROM #temp2
In other words:
Create temp table
Execute proc
Select from temp table
Here is complete example:
CREATE PROC prTest2 #var VARCHAR(100)
AS
EXEC (#var)
GO
CREATE TABLE #temp (id INT)
EXEC prTest2 'insert #temp values(1)'
SELECT *
FROM #temp
1st Method - Enclose multiple statements in the same Dynamic SQL Call:
DECLARE #DynamicQuery NVARCHAR(MAX)
SET #DynamicQuery = 'Select * into #temp from (select * from tablename) alias
select * from #temp
drop table #temp'
EXEC sp_executesql #DynamicQuery
2nd Method - Use Global Temp Table:
(Careful, you need to take extra care of global variable.)
IF OBJECT_ID('tempdb..##temp2') IS NULL
BEGIN
EXEC (
'create table ##temp2 (id int)
insert ##temp2 values(1)'
)
SELECT *
FROM ##temp2
END
Don't forget to delete ##temp2 object manually once your done with it:
IF (OBJECT_ID('tempdb..##temp2') IS NOT NULL)
BEGIN
DROP Table ##temp2
END
Note: Don't use this method 2 if you don't know the full structure on database.
I had the same issue that #Muflix mentioned. When you don't know the columns being returned, or they are being generated dynamically, what I've done is create a global table with a unique id, then delete it when I'm done with it, this looks something like what's shown below:
DECLARE #DynamicSQL NVARCHAR(MAX)
DECLARE #DynamicTable VARCHAR(255) = 'DynamicTempTable_' + CONVERT(VARCHAR(36), NEWID())
DECLARE #DynamicColumns NVARCHAR(MAX)
--Get "#DynamicColumns", example: SET #DynamicColumns = '[Column1], [Column2]'
SET #DynamicSQL = 'SELECT ' + #DynamicColumns + ' INTO [##' + #DynamicTable + ']' +
' FROM [dbo].[TableXYZ]'
EXEC sp_executesql #DynamicSQL
SET #DynamicSQL = 'IF OBJECT_ID(''tempdb..##' + #DynamicTable + ''' , ''U'') IS NOT NULL ' +
' BEGIN DROP TABLE [##' + #DynamicTable + '] END'
EXEC sp_executesql #DynamicSQL
Certainly not the best solution, but this seems to work for me.
I would strongly suggest you have a read through http://www.sommarskog.se/arrays-in-sql-2005.html
Personally I like the approach of passing a comma delimited text list, then parsing it with text to table function and joining to it. The temp table approach can work if you create it first in the connection. But it feel a bit messier.
Result sets from dynamic SQL are returned to the client. I have done this quite a lot.
You're right about issues with sharing data through temp tables and variables and things like that between the SQL and the dynamic SQL it generates.
I think in trying to get your temp table working, you have probably got some things confused, because you can definitely get data from a SP which executes dynamic SQL:
USE SandBox
GO
CREATE PROCEDURE usp_DynTest(#table_type AS VARCHAR(255))
AS
BEGIN
DECLARE #sql AS VARCHAR(MAX) = 'SELECT * FROM INFORMATION_SCHEMA.TABLES WHERE TABLE_TYPE = ''' + #table_type + ''''
EXEC (#sql)
END
GO
EXEC usp_DynTest 'BASE TABLE'
GO
EXEC usp_DynTest 'VIEW'
GO
DROP PROCEDURE usp_DynTest
GO
Also:
USE SandBox
GO
CREATE PROCEDURE usp_DynTest(#table_type AS VARCHAR(255))
AS
BEGIN
DECLARE #sql AS VARCHAR(MAX) = 'SELECT * INTO #temp FROM INFORMATION_SCHEMA.TABLES WHERE TABLE_TYPE = ''' + #table_type + '''; SELECT * FROM #temp;'
EXEC (#sql)
END
GO
EXEC usp_DynTest 'BASE TABLE'
GO
EXEC usp_DynTest 'VIEW'
GO
DROP PROCEDURE usp_DynTest
GO
This is my first time posting on SO, so please go easy!
I'm attempting to write a SQL script that queries the same table for a list of databases in a single SQL Server instance.
I have successfully queried the list of databases that I required using the following, and inserting this data into a temp table.
Select name Into #Versions
From sys.databases
Where name Like 'Master%'
Master is suffixed with numerical values to identify different environments.
Select * From #Versions
Drop Table #Versions
The table name I am trying to query, is the same in each of the databases, and I want to extract the newest value from this table and insert it into the temp table for each of the database names returned.
I have tried researching this but to no avail. I am fairly comfy with SQL but I fear I could be out of my depth here.
You can do the following. Once you have the list of your databases, you can build up the query (you need to edit it for your purpose).
Select name Into #Versions
From sys.databases
Where name Like 'test%'
declare #sql as varchar(max) = ''
select #sql = #sql + 'INSERT INTO sometable SELECT TOP 1 * FROM ' + name + '..sourcetable ORDER BY somedate DESC; '
FROM #Versions
exec (#sql)
Drop Table #Versions
Look at The undocumented sp_MSforeachdb procedure and here
I ran a sp in SSMS and it gathers information from 50+ databases with the exact same structure. I am pulling results such as CustomerName, NumberOfUsers and VersionofCode. When I execute the procedure, I get 50+ different result sets, all with the same columns selected. Instead of exporting these 50+ times and putting it together in a single excel sheet, I'd like to see if I can export all results to 1 excel file.
Is this possible? I would have to think there would be a way to do this as my column names match up for every database I am querying.
Any help is appreciated!
There are probably a number of ways to solve this problem. I would address the issue by attempting to merge the many result sets from your stored procedure calls into a single result set and then perform whatever output-export (to excel) that you wish to do.
Simplest method would be to use a temp table to accumulate the results from each stored proc call. You can use the "INSERT #temptable EXEC mystoredproc #param1" syntax to store the results of a stored proc.
Here's a little example I whipped up:
-- *** Create a sample stored proc that returns one result set ***
CREATE PROC spGetCompanyEmployees #pCompanyID AS INT
AS
BEGIN
SELECT Company.CompanyName
, Department.DepartmentName
, Employee.EmployeeName
FROM Company
LEFT JOIN Department ON Department.CompanyID = Company.CompanyID
LEFT JOIN Employee ON Employee.DepartmentID = Department.DepartmentID
WHERE Company.CompanyID = #pCompanyID
END
GO
-- *** Demonstrate how to call that stored proc multiple times,
-- *** accumulating the results in a temp table and selecting
-- *** the combined results at the end.
CREATE TABLE #ttbl
(
CompanyName NVARCHAR(60)
, DepartmentName NVARCHAR(60)
, EmployeeName NVARCHAR(60)
)
INSERT #ttbl
EXEC spGetCompanyEmployees 1
INSERT #ttbl
EXEC spGetCompanyEmployees 2
SELECT * FROM #ttbl
The resulting output from that final SELECT will be a combined, single result set from both stored procedure calls.
I hope this helps.
I combined the suggestion to use a temp table with an example from this blog post that uses sys.sp_msforeachdb to iterate through databases, resulting in the following:
Create TABLE #temp
(
DbName NVARCHAR(50),
TableName NVARCHAR(50)
)
INSERT #temp
EXEC
sys.sp_msforeachdb
'SELECT ''?'' DatabaseName, Name FROM [?].sys.Tables WHERE Name LIKE ''%sometablename%'''
Select * from #temp
I want a program to access a table/view/stored procedure, etc. (something materialized, let's call it X) that abstracts the real location of the data contained in three basic tables (the tables have the same definition in all locations).
I would want X to fetch the server name, catalog name and table name from somewhere (a table, probably) and access the specific three basic tables. The caller of X would not know which specific tables were being called.
How can I do this in SQL Server (2008)?
Like a function, a view can't use dynamic SQL - it can't go find some metadata reference somewhere and adjust accordingly.
I think the closest thing to what you want is a synonym. Let's say you have three different databases, A, B and C. In A the table you want the view to reference is dbo.foo, in B it is dbo.bar, and in Cit is dbo.splunge. So then you could create a synonym like so in each database:
USE A;
GO
CREATE SYNONYM dbo.YourCommonViewName FOR dbo.foo;
GO
USE B;
GO
CREATE SYNONYM dbo.YourCommonViewName FOR dbo.bar;
GO
USE C;
GO
CREATE SYNONYM dbo.YourCommonViewName FOR dbo.splunge;
GO
Now this technically isn't a view, but in each database you can say...
SELECT <cols> FROM dbo.YourCommonViewName;
...and it will return the data from the database-specific table.
To do this in a stored procedure would be much simpler. Say you store the server, database and table name in some table, e.g. dbo.lookup:
CREATE TABLE dbo.lookup
(
id INT PRIMARY KEY,
[server] SYSNAME,
[database] SYSNAME,
[table] SYSNAME,
active BIT NOT NULL DEFAULT (0)
);
-- you may want a constraint or trigger to ensure
-- only one row can be active at any one time.
INSERT dbo.lookup(id, [server], [database], [table])
SELECT 1,N'serverA',N'databaseA',N'tableA'
UNION ALL SELECT 2,N'serverB',N'databaseB',N'tableB';
Now your program can say:
UPDATE dbo.lookup SET active = 1 WHERE ... ?
And your stored procedure can be:
CREATE PROCEDURE dbo.whatever
AS
BEGIN
SET NOCOUNT ON;
DECLARE #sql NVARCHAR(MAX);
SELECT #sql = N'SELECT <cols> FROM ' + QUOTENAME([server])
+ '.' + QUOTENAME([database]) + '.dbo.' + QUOTENAME([table])
FROM dbo.lookup WHERE active = 1;
EXEC sp_executesql #sql;
END
GO
I still don't understand the point, and I don't know what you're planning to do when two different users expect to call your program at the same time, and they each should get results from a different location.
Agreed with Aaron on the fact that views and functions cannot use dynamic sql.
Still what you can do is build a clr table valued function. In that you can play with .net code and query whatever you want. And build you data accordingly and output what you need.
So instead of querying the data like
select * from myview
you can query it
select * from dbo.clr_mymockupview()
Create SYNONYMs to your remote servers.
Create your VIEW to concatenate your locations together using UNION ALL.
Since you said "tables", join your tables before the UNION ALL and hopefully, MS will perform the JOIN remotely.
Use a union query with parameters for database, server, and catalog:
Select col1, col2, <etc.>, 'table1' as tablename, 'server1' as servername, 'catalog1' as catname from server1.catalog1.table1
Union Select col1, col2, <etc.>, 'table2' as tablename, 'server2' as servername, 'catalog2' as catname from server2.catalog2.table2
Union Select col1, col2, <etc.>, 'table3' as tablename, 'server3' as servername, 'catalog3' as catname from server3.catalog3.table3
Then filter based on your 3 criteria. This probably won't be blazing fast but will wonk with std. SQL.
Brief history:
I'm writing a stored procedure to support a legacy reporting system (using SQL Server Reporting Services 2000) on a legacy web application.
In keeping with the original implementation style, each report has a dedicated stored procedure in the database that performs all the querying necessary to return a "final" dataset that can be rendered simply by the report server.
Due to the business requirements of this report, the returned dataset has an unknown number of columns (it depends on the user who executes the report, but may have 4-30 columns).
Throughout the stored procedure, I keep a column UserID to track the user's ID to perform additional querying. At the end, however, I do something like this:
UPDATE #result
SET Name = ppl.LastName + ', ' + ppl.FirstName
FROM #result r
LEFT JOIN Users u ON u.id = r.userID
LEFT JOIN People ppl ON ppl.id = u.PersonID
ALTER TABLE #result
DROP COLUMN [UserID]
SELECT * FROM #result r ORDER BY Name
Effectively I set the Name varchar column (that was previously left NULL while I was performing some pivot logic) to the desired name format in plain text.
When finished, I want to drop the UserID column as the report user shouldn't see this.
Finally, the data set returned has one column for the username, and an arbitrary number of INT columns with performance totals. For this reason, I can't simply exclude the UserID column since SQL doesn't support "SELECT * EXCEPT [UserID]" or the like.
With this known (any style pointers are appreciated but not central to this problem), here's the problem:
When I execute this stored procedure, I get an execution error:
Invalid column name 'userID'.
However, if I comment out my DROP COLUMN statement and retain the UserID, the stored procedure performs correctly.
What's going on? It certainly looks like the statements are executing out of order and it's dropping the column before I can use it to set the name strings!
[Edit 1]
I defined UserID previously (the whole stored procedure is about 200 lies of mostly irrelevant logic, so I'll paste snippets:
CREATE TABLE #result ([Name] NVARCHAR(256), [UserID] INT);
Case sensitivity isn't the problem but did point me to the right line - there was one place in which I had userID instead of UserID. Now that I fixed the case, the error message complains about UserID.
My "broken" stored procedure also works properly in SQL Server 2008 - this is either a 2000 bug or I'm severely misunderstanding how SQL Server used to work.
Thanks everyone for chiming in!
For anyone searching this in the future, I've added an extremely crude workaround to be 2000-compatible until we update our production version:
DECLARE #workaroundTableName NVARCHAR(256), #workaroundQuery NVARCHAR(2000)
SET #workaroundQuery = 'SELECT [Name]';
DECLARE cur_workaround CURSOR FOR
SELECT COLUMN_NAME FROM [tempdb].INFORMATION_SCHEMA.Columns WHERE TABLE_NAME LIKE '#result%' AND COLUMN_NAME <> 'UserID'
OPEN cur_workaround;
FETCH NEXT FROM cur_workaround INTO #workaroundTableName
WHILE ##FETCH_STATUS = 0
BEGIN
SET #workaroundQuery = #workaroundQuery + ',[' + #workaroundTableName + ']'
FETCH NEXT FROM cur_workaround INTO #workaroundTableName
END
CLOSE cur_workaround;
DEALLOCATE cur_workaround;
SET #workaroundQuery = #workaroundQuery + ' FROM #result ORDER BY Name ASC'
EXEC(#workaroundQuery);
Thanks everyone!
A much easier solution would be to not drop the column, but don't return it in the final select.
There are all sorts of reasons why you shouldn't be returning select * from your procedure anyway.
EDIT: I see now that you have to do it this way because of an unknown number of columns.
Based on the error message, is the database case sensitive, and so there's a difference between userID and UserID?
This works for me:
CREATE TABLE #temp_t
(
myInt int,
myUser varchar(100)
)
INSERT INTO #temp_t(myInt, myUser) VALUES(1, 'Jon1')
INSERT INTO #temp_t(myInt, myUser) VALUES(2, 'Jon2')
INSERT INTO #temp_t(myInt, myUser) VALUES(3, 'Jon3')
INSERT INTO #temp_t(myInt, myUser) VALUES(4, 'Jon4')
ALTER TABLE #temp_t
DROP Column myUser
SELECT * FROM #temp_t
DROP TABLE #temp_t
It says invalid column for you. Did you check the spelling and ensure there even exists that column in your temp table.
You might try wrapping everything preceding the DROP COLUMN in a BEGIN...COMMIT transaction.
At compile time, SQL Server is probably expanding the * into the full list of columns. Thus, at run time, SQL Server executes "SELECT UserID, Name, LastName, FirstName, ..." instead of "SELECT *". Dynamically assembling the final SELECT into a string and then EXECing it at the end of the stored procedure may be the way to go.