Snowflake: argument 1 to function SYSTEM$ABORT_TRANSACTION needs to be constant - snowflake-cloud-data-platform

The snowflake statement:
select system$abort_transaction(id) from values (10) as transactions(id);
Throws an SQL compilation error:
SQL compilation error: argument 1 to function SYSTEM$ABORT_TRANSACTION needs to be constant, found 'TRANSACTIONS.ID'
Is there a workaround or it should be fixed by snowflake devs?
UPD: I should have provided more context earlier. What I want to do to abort all active transactions. Something like that:
show transactions;
select system$abort_transaction("id"::int) from table(RESULT_SCAN (LAST_QUERY_ID()));
UPD2:
The following queries are executed just fine:
show transactions;
select dateadd(millisecond, "id"::int, current_date()) from table(RESULT_SCAN (LAST_QUERY_ID()));

The problem is self-explanatory from the error message. Try using a variable as the argument (this works for single ids).
SET v_id = (select "id" from table(RESULT_SCAN (LAST_QUERY_ID())) as t);
select SYSTEM$ABORT_TRANSACTION($v_id);
You need to either construct it dynamically using a stored procedure if you want to run for multiple values. It can also be automated by generating the SELECT statements. You would then have to use SnowSQL command line like interface to run the generated script.

The problem here seems to be with the parameter being passed to the System Control Function system$abort_transaction(). As mentioned by #NickW in the comments, the parameter that should be passed is the identifier for the transaction to abort. It appears that id in your code is the parameter you passed, whereas this should be a number.

Related

Does SQL Server deferred name resolution work for functions?

SQL Server has Deferred Name Resolution feature, read here for details:
https://msdn.microsoft.com/en-us/library/ms190686(v=sql.105).aspx
In that page, all it's talking is stored procedure so it seems Deferred Name Resolution only works for stored procedures and not for functions and I did some testing.
create or alter function f2(#i int)
returns table
as
return (select fff from xxx)
go
Note the table xxx does not exist. When I execute the above CREATE statement, I got the following message:
Msg 208, Level 16, State 1, Procedure f2, Line 4 [Batch Start Line 22]
Invalid object name 'xxx'.
It seems that SQL Server instantly found the non-existent table xxx and it proved Deferred Name Resolution doesn't work for functions. However when I slightly change it as follows:
create or alter function f1(#i int)
returns int
as
begin
declare #x int;
select #x = fff from xxx;
return #x
end
go
I can successfully execute it:
Commands completed successfully.
When executing the following statement:
select dbo.f1(3)
I got this error:
Msg 208, Level 16, State 1, Line 34
Invalid object name 'xxx'.
So here it seems the resolution of the table xxx was deferred. The most important differences between these two cases is the return type. However I can't explain when Deferred Name Resolution will work for functions and when not. Can anyone help me to understand this? Thanks in advance.
It feels like you were looking for understanding of why your particular example didn't work. Quassnoi's answer was correct but didn't offer a reason so I went searching and found this MSDN Social answer by Erland Sommarskog. The interesting part:
However, it does not extend to views and inline-table functions. For
stored procedures and scalar functions, all SQL Server stores in the
database is the text of the module. But for views and inline-table
functions (which are parameterised view by another name) SQL Server
stores metadata about the columns etc. And that is not possible if the
table is missing.
Hope that helps with understanding why :-)
EDIT:
I did take some time to confirm Quassnoi's comment that sys.columns as well as several other tables did contain some metadata about the inline function so I am unsure if there is other metadata not written. However I thought I would add a few other notes I was able to find that may help explain in conjunction.
First a quote from Wayne Sheffield's blog:
In the MTVF, you see only an operation called “Table Valued Function”. Everything that it is doing is essentially a black box – something is happening, and data gets returned. For MTVFs, SQL can’t “see” what it is that the MTVF is doing since it is being run in a separate context. What this means is that SQL has to run the MTVF as it is written, without being able to make any optimizations in the query plan to optimize it.
Then from the SQL Server 2016 Exam 70-761 by Itzik Ben-Gan (Skill 3.1):
The reason that it's called an inline function is because SQL Server inlines, or expands, the inner query definition, and constructs an internal query directly against the underlying tables.
So it seems the inline function essentially returns a query and is able to optimize it with the outer query, not allowing the black-box approach and thus not allowing deferred name resolution.
What you have in your first example is an inline function (it does not have BEGIN/END).
Inline functions can only be table-valued.
If you used a multi-statement table-valued function for you first example, like this:
CREATE OR ALTER FUNCTION
fn_test(#a INT)
RETURNS #ret TABLE
(
a INT
)
AS
BEGIN
INSERT
INTO #ret
SELECT a
FROM xxx
RETURN
END
, it would compile alright and fail at runtime (if xxx would not exist), same as a stored procedure or a scalar UDF would.
So yes, DNR does work for all multi-statement functions (those with BEGIN/END), regardless of their return type.

Dynamically Create Views from parameters/variables SQL SSIS

I have a table that contains just under a million rows. I'm building a form using SSIS that asks for user input and uses the values as parameters to build a view from source data. I'm having trouble getting SSIS to create the view from a variable.
The purpose of this 'tool' is to provide a dialogue that programmatically builds a view and later an update statement based upon parameters defined via a form that will execute an SSIS package. A number of the ppl on my team know 0 SQL. Therefore this circumvents any SQL knowledge. Creating an entirely standalone app is not ideal as it would require too much additional overhead on my side and would deviate from a number of our existing processes that currently use SSIS/SQL to achieve similar results.
With that here is what I've tried/trying.
I have an SSIS package that contains 'Execute SQL Task'
This task brings up a form with 5 inputs (variables)
var1,var2,var3,var4,var5.
some vars are strings others are doubles, ints etc... (they all vary)
You populate the fields and hit okay.
These variables are passed to an 'Execute Package Task'.
Inside this package (Package B)
the vars are used in an 'Execute SQL Task'.
This task is attempting to take the users input and create a view with a where clause containing 4 other variables.
example:
Create View ? AS Select col1,col2,col3,col4 WHERE
col1 = ?
AND col2 =?
AND col3 =?.........
First it appears that using ? in the create view is invalid.
The error being:
Error: 0x0 at Build_Query: Incorrect syntax near '#P1'.
Error: 0xC002F210 at Build_Query, Execute SQL Task: Executing the query "CREATE VIEW ? as Select * from S_t_equip_template
..." failed with the following error: "The batch could not be analyzed because of compile errors.". Possible failure reasons: Problems with the query, "ResultSet" property not set correctly, parameters not set correctly, or connection not established
correctly.
Task failed: Build_Query
If I use the create view variable as an expression and remove the variables/paramerters for the where statements, I can create the view no problem.
However the where statements throw errors once I add them back in. I've tried evaluating these as an expression in the 'Execute SQL Task' but as these are of various types I get the error:
[Execute SQL Task] Error: Executing the query "
CREATE VIEW testing AS SELECT
P.label,P.uniq..." failed with the following error: "The metadata could not
be determined because statement 'CREATE VIEW testingagain AS SELECT
P.label,P.uniqueid,C.label as Child_Label,C.uniqueid as Child_uni' does not
support metadata discovery.". Possible failure reasons: Problems with the
query, "ResultSet" property not set correctly, parameters not set correctly,
or connection not established correctly.
No idea what is going on. Any help would be appreciated
I've googled the error and found some info but the other use-cases are so different that it's difficult to understand the actual cause, or another work around.
AS requested (simplified example):
I've created a package variable (datatype string) called: View_Name
Execute SQL Task:
CREATE VIEW #[User::View_Name] AS SELECT
* from table1
where col1 = 100;
Specifically it does not like that I use a variable here.
If I set the View name everything works until: I move on to my Where clauses that contain variables.
Create a variable called type (datatype int)
I map the variable/parameter in my sql task
Example:
CREATE VIEW tempTable AS SELECT
* from table1
where col1 = ?;
This won't work, same error.
If i attempt to do the above via an expression or expressions I get the following error
[Execute SQL Task] Error: Executing the query "CREATE VIEW test_45678 AS SELECT P.label,P.uniquei..." failed with the following error: "Must declare the scalar variable "#".". Possible failure reasons: Problems with the query, "ResultSet" property not set correctly, parameters not set correctly, or connection not established correctly.
Generally having to due with the variables cannot be evaluated this way. I'm guessing I'd need to evaluate each piece individually and build the expression piece by piece. That's fine but very inefficient and not maintainable.
I had some fundamental misunderstanding in my attempt to evaluate my expressions. Specifically syntax issues and having to cast each variable to a string.
My SQLstatement variable
ON C.pid = P.ID
where
C.width >="+(DT_WSTR, 8)#[User::Width] +"-"+ (DT_WSTR, 8)#[User::Range]+........
The final expression looks like so:
"Create View "+#[User::View_Name] + " AS SELECT " + #[User::SQLStatement]

Issue loading-data-from-multiple-db-to-another-server-using-ssis

I am facing issue in loading-data-from-multiple-db-to-another-server-using-ssis
I have referred the below link
Loading data from multiple db to another server using SSIS
SSIS Package FLow :
Unfortunately i am getting the error in "Execute SQL Task" as below:
[Execute SQL Task] Error: There is an invalid number of result
bindings returned for the ResultSetType: "ResultSetType_Rowset".
Appreciate if you could help me with the solutions.
Thanks
Based on the comments, to solve your issue
1. Evaluate your SQL Statement. For instance :
2. Once your variable query is evaluating, move to Execute SQL Task. It should look like this:
3. Next the resultSet should look like this (object_variable is of object type)
Why are we not using anything in parameter mapping ?
Answer: If we had a SQL query like Select col1, col2 from table1 where col3 = ?, Then we would be replacing ? with either a parameter or a variable.
In your case, delete everything inside parameter mapping.
Updated : Also, since you're query is Select * into tbl2 from tbl1, ResultSet property should be None instead of any other thing.
You have 2 Execute SQL Tasks
1, First Execute SQL Task, get list of tables and schema, it expects a Full Result set and map it to a object type variable.
2, Foreach loop container, ADO Enumerator, ADO source is the object type variable. Variable Mappings to 2 string type variables, 1 is for table name and 1 is for schema name.
Second Execute SQL Task, it has no Full Result set, no parameter mapping. Because table name/schema name changes are taken care of by Foreach loop container.

Why does executing a scalar function result in a "create function" operation?

I needed to trim a number of strings in a select statement, so instead of repeating multiple ltrim(rtrim(' the string ') calls, I created a simple trim function as follows:
create function dbo.trim(#String varchar(max))
returns varchar(max)
as
begin
return rtrim(ltrim(#String))
end
go
However, during the execution of my select (which invokes the function multiple times) I run the following select in a different window as sa:
SELECT sqltext.TEXT,
req.session_id,
req.status,
req.command,
req.cpu_time,
req.total_elapsed_time
FROM sys.dm_exec_requests req
CROSS APPLY sys.dm_exec_sql_text(sql_handle) AS sqltext
and observe the following
TEXT session_id status command cpu_time total_elapsed_time
------------------------------------------------------------------
** 99 running SELECT 12045 12388
where the first column (replaced by ** above for readability) contains the following:
create function dbo.trim(#String varchar(max))
returns varchar(max)
as
begin
return rtrim(ltrim(#String))
end
Am I correctly interpreting this to mean that upon calling the trim function that SQL Server actually calls a create?
As you can see from the table above, the execution time is rather long and in some cases I've found the create operation to outright hang thus blocking the completion of the select and further write operations on the database such that I've had to kill the operation.
Can anyone shed some light on this?
Thanks!
Pab
Am I correctly interpreting this to mean that upon calling the trim
function that SQL Server actually calls a create?
No, SQL Server just shows you the full text of the SQL Module - which includes the CREATE. You can use statement_start_offset and statement_end_offset to see the statement actually being executed.
SideNote: You're better off not using scalar UDFs for something trivial like a TRIM function. These have well known performance problems. See Converting A Scalar User Defined Function To A Inline Table Valued Function for an alternative approach if this is worth encapsulating in a function at all.

Execute sql task mapping variables in ssis

INSERT INTO [DEV_BI].dbo.[DimAktivitet]([Beskrivning],[företag],[Projektnummer],[Aktivitet],
loaddate)
SELECT NULL,
a.DATAAREAID,
a.PROJID,
a.MID_ACTIVITYNUMBER,
GETDATE()
FROM [?].dbo.[v_ProjCostTrans_ProjEmplTrans] a
LEFT OUTER JOIN [DEV_BI] .dbo.[DimAktivitet] b ON a.MID_ACTIVITYNUMBER = b.Aktivitet
AND a.DataAreaID = b.företag
AND a.ProjID = b.Projektnummer
WHERE b.Aktivitet_key IS NULL
I have this above sql code in execute sql task and in the parameter mapping i have mapped a variable named user::connectionstring with data type nvarchar , parameter name = 0. Im getting this following error.
[Execute SQL Task] Error: Executing the query "insert into [DEV_BI].dbo.[DimAktivitet]([Beskrivni..." failed with the following error: "Invalid object name '?.dbo.v_ProjCostTrans_ProjEmplTrans'.". Possible failure reasons: Problems with the query, "ResultSet" property not set correctly, parameters not set correctly, or connection not established correctly.
please someone help me to solve this.
It appears you are trying to change the database based on a variable. The Execute SQL Task can only use parameters as filters in the WHERE clause. This behavior is described in this TechNet article. For instance, you could do this:
insert into [DEV_BI].dbo.[DimAktivitet]([Beskrivning],[företag],[Projektnummer],[Aktivitet],loaddate)
select null,a.DATAAREAID,a.PROJID,a.MID_ACTIVITYNUMBER,GETDATE() from
[DEV_BI].dbo.[v_ProjCostTrans_ProjEmplTrans] a
left outer join
[DEV_BI] .dbo.[DimAktivitet] b
on a.MID_ACTIVITYNUMBER = b.Aktivitet AND a.DataAreaID = b.företag AND a.ProjID = b.Projektnummer
where b.Aktivitet_key is null
AND b.SomeFilterCriteria = ?;
If you really want to vary the database based on a variable, then you have three options:
Vary the Connection Manager connection string to your database connection based on an expression as described in a blog post. This is the best solution if you are only changing the database and nothing else.
Generate the entire SQL code as a variable and execute a variable as the SQL command instead of passing variables to the Execute SQL Command. This is described in this blog post under the section "Passing in the SQL Statement from a Variable".
Create a stored procedure, pass the parameter to the stored procedure, and let it generate the SQL it needs on the fly.

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