I am trying to assign all the table names of a schema to a variable. Later, I wish to create an update trigger for each table.
I am extracting the tables using :
select table_name from information_schema.tables;
when I do the following, I get null values:
declare #tablename nvarchar(max)
select table_name = #tablename from information_schema.tables;
I am using mssql in SSMS2016, can someone please tell me how I can assign the table names to a variable?
It is a really good question, if it is a good idea to create a trigger for each and any table, but - whenever I need to create statements - I suggest this:
select CONCAT('CREATE TRIGGER ',QUOTENAME(CONCAT(table_name,'_trigger')),' ON ',QUOTENAME(table_name),' AFTER UPDATE AS BEGIN PRINT ''yeah!''; END',CHAR(13),CHAR(10),'GO' )
from information_schema.tables
where TABLE_TYPE='BASE TABLE';
Send the output to text and you get:
CREATE TRIGGER [SomeTable_trigger] ON [SomeTable] AFTER UPDATE AS BEGIN PRINT 'yeah!'; END
GO
CREATE TRIGGER [Another_trigger] ON [Another] AFTER UPDATE AS BEGIN PRINT 'yeah!'; END
GO
... more of this...
GO
...
The next step was to copy all these statements to a new query window and adapt them to your needs.
Related
My program will create a temp table which will drop after the program executed. The data type length is 8. But I want to change the length to 15 when I run the program using the trigger function in Sql Server. I have few table that need to change the length. Is there any way to change the length without stating the table name in trigger function?
Clarification:
I have 100 programs which will create temporary table with different names. Each temp table will have user_id varchar(8). So i want to change the length to 15 . But i dont want to open my each program's source code to change it. is there a better way that you can suggest me?
What you want is essentially possible to achive using DDL triggers.
CREATE TRIGGER [TRG_TABLES]
ON DATABASE
AFTER
CREATE_TABLE
AS
BEGIN
SET NOCOUNT ON
DECLARE #TABLE_NAME SYSNAME
SELECT
#TABLE_NAME = EVENTDATA().value('(/EVENT_INSTANCE/ObjectName)[1]','SYSNAME')
IF EXISTS(SELECT * FROM INFORMATION_SCHEMA.COLUMNS
WHERE TABLE_NAME = #TABLE_NAME
AND COLUMN_NAME = 'TEST')
BEGIN
DECLARE #SQL as NVARCHAR(MAX) ='ALTER TABLE ' + #TABLE_NAME + ' ALTER COLUMN TEST NVARCHAR(200) '
Exec sp_ExecuteSql #SQL
END
END
GO
ENABLE TRIGGER [TRG_TABLES] ON DATABASE
You should be EXTRA careful about SQL injection if you use this approach.
EDIT: This is just a general idea you should probably figure out under which conditions you should alter the column - if there is a predictable pattern to your table names.
I am generating dynamic script to move data into another database if table is not present then i want to create. This script runs perfectly if it execute directly. But gives error if that script string execute by execute statement. i have tried exec also.
declare #temp as varchar(max)
set #temp='select * into Allocation_Archive.dbo.Users from Users'
execute #temp
Error
Database 'select * into Allocation_Archive' does not exist. Make sure that the name is entered correctly.
Option 1
Add a USE database statement to your variable or specify the full object name including database and schema.
Wrap the #temp variable in parentheses
For example:
declare #temp as varchar(max)
set #temp='select * into Allocation_Archive.dbo.Users from ThisDatabase.dbo.Users'
execute #temp
Option 2
Don't use:
EXECUTE #temp
Instead use
EXEC sp_executesql #temp
You will also need to change your #temp variable to be nvarchar(max)
I have several stored procedures in my database, structured like this:
CREATE PROCEDURE MyProcedure (.....)
AS
DECLARE #myvar NVARCHAR(100);
SET #myvar = (SELECT .... FROM my_table WHERE ....)
GO
I was asked to replace the table my_table in the FROM clause with another one in every procedure that has it.
I went through a lot of researches, but I should create a script that works by itself, and I haven't found anything suitable. For example I found the sp_helpTetx that shows the source code of a stored procedure, but is there a way to put it into a variable in order to edit it?
You can use tool like REDGATE SqlRefactor that works perfectly or you can script all the stored procedures, replace CREATE command with ALTER and then apply the other REPLACE in text you need...
I do it lot of time, you have to pay attention but it works...
Find all stored procedures with a reference to that table (you can either use the dependencies stuff built into SQL Server or run a query looking for that table name see Search text in stored procedure in SQL Server)
Script them out with an "ALTER" instead of "CREATE" Press CTRL-H (find and replace)
Execute the script.
Here is an article outlining how to handle this using a cursor, and the sp_HelpText as mentioned above (including set as also mentioned).
http://www.ideosity.com/ourblog/post/ideosphere-blog/2013/06/14/how-to-find-and-replace-text-in-all-stored-procedures
-- set "Result to Text" mode by pressing Ctrl+T
SET NOCOUNT ON
DECLARE #sqlToRun VARCHAR(1000), #searchFor VARCHAR(100), #replaceWith VARCHAR(100)
-- text to search for
SET #searchFor = '[MY-SERVER]'
-- text to replace with
SET #replaceWith = '[MY-SERVER2]'
-- this will hold stored procedures text
DECLARE #temp TABLE (spText VARCHAR(MAX))
DECLARE curHelp CURSOR FAST_FORWARD
FOR
-- get text of all stored procedures that contain search string
-- I am using custom escape character here since i need to espape [ and ] in search string
SELECT DISTINCT 'sp_helptext '''+OBJECT_SCHEMA_NAME(id)+'.'+OBJECT_NAME(id)+''' '
FROM syscomments WHERE TEXT LIKE '%' + REPLACE(REPLACE(#searchFor,']','\]'),'[','\[') + '%' ESCAPE '\'
ORDER BY 'sp_helptext '''+OBJECT_SCHEMA_NAME(id)+'.'+OBJECT_NAME(id)+''' '
OPEN curHelp
FETCH next FROM curHelp INTO #sqlToRun
WHILE ##FETCH_STATUS = 0
BEGIN
--insert stored procedure text into a temporary table
INSERT INTO #temp
EXEC (#sqlToRun)
-- add GO after each stored procedure
INSERT INTO #temp
VALUES ('GO')
FETCH next FROM curHelp INTO #sqlToRun
END
CLOSE curHelp
DEALLOCATE curHelp
-- find and replace search string in stored procedures
-- also replace CREATE PROCEDURE with ALTER PROCEDURE
UPDATE #temp
SET spText = REPLACE(REPLACE(spText,'CREATE PROCEDURE', 'ALTER PROCEDURE'),#searchFor,#replaceWith)
SELECT spText FROM #temp
-- now copy and paste result into new window
-- then make sure everything looks good and run
GO
If sp_HelpText returns a table, why not you use a cursor to loop over the results and join the resulting strings together? It's nasty, but would do the trick.
I have to create a stored procedure where I will pass tableName, columnName, id as parameters. The task is to select records from the passed table where columnName has passed id. If record is found update records with some fixed data. Also implement Transaction so that we can rollback in case of any error.
There are hundreds of table in database and each table has different schema that is why I have to pass columnName.
Don't know what is the best approach for this. I am trying select records into a temp table so that I can manipulate it as per requirement but its not working.
I am using this code:
ALTER PROCEDURE [dbo].[GetRecordsFromTable]
#tblName nvarchar(128),
#keyCol varchar(100),
#key int = 0
AS
BEGIN
SET NOCOUNT ON;
BEGIN TRY
--DROP TABLE #TempTable;
DECLARE #sqlQuery nvarchar(4000);
SET #sqlQuery = 'SELECT * FROM ' + #tblName + ' WHERE ' + #keyCol + ' = 2';
PRINT #sqlQuery;
INSERT INTO #TempTable
EXEC sp_executesql #sqlQuery,
N'#keyCol varchar(100), #key int', #keyCol, #key;
SELECT * FROM #TempTable;
END TRY
BEGIN CATCH
EXECUTE [dbo].[uspPrintError];
END CATCH;
END
I get an error
Invalid object name '#TempTable'
Also not sure if this is the best approach to get data and then update it.
If you absolutely must make that work then I think you'll have to use a global temp table. You'll need to see if it exists before running your dynamic sql and clean up. With a fixed table name you'll run into problems with other connections. Inside the dynamic sql you'll add select * into ##temptable from .... Actually I'm not even sure why you want the temp table in the first place. Can't the dynamic sql just return the results?
On the surface it seems like a solid idea to have one generic procedure for returning data with a couple of parameters to drive it but, without a lot of explanation, it's just not the way database are designed to work.
You should create the temp table.
IF OBJECT_ID('tempdb..##TempTable') IS NOT NULL
DROP TABLE ##TempTable
CREATE TABLE ##TempTable()
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