I have a Table function which returns a set of rows based on a parameter, which looks like this example:
CREATE FUNCTION fn_get_records
(#PARENTID INT)
RETURNS #returnTable TABLE
(
-- columns returned by the function
Id INT NOT NULL,
Parent_Id INT NOT NULL,
Name VARCHAR(255) NOT NULL
)
AS
BEGIN
-- This select returns data
INSERT INTO #returnTable (Id, ParentId, Name)
SELECT Id, ParentId, Name FROM [whatever] where Parent_Id = #PARENTID
RETURN
END
I have another table which contains a list of those "Parent Ids" and I should call the previous function for each Parent_Id that matches a specific query and aggregate all results.
The parent Ids are retrieved using something like
SELECT Parent_Id
FROM Parent_Records
WHERE Country = 'USA'
This select returns, for example, 4 rows. For each row I have to execute my function fn_get_records and aggregate all results together in a view or in another function.
Is it even possible?
Of course I don't want to use cursors because I need something fast
Just a quick FYI: A more efficient TVF would be a single statement
CREATE FUNCTION fn_get_records (#PARENTID INT)
RETURNS TABLE
AS
RETURN (
SELECT Id, ParentId, Name FROM [whatever] where Parent_Id = #PARENTID
)
END
Then you can call your function via a CROSS Apply. For Example:
Select A.*
,B.*
From YourTable A
Cross Apply dbo.fn_get_records (A.SomeIntValue) B
Related
We are running a table that holds some information for order of new products.
From time to time we receive new orders from a 3rd party system and insert them into our DB.
Sometimes, however, for a specific order there is already an entry in our table.
So instead of checking if there already IS an order, the colleagues just inserts new data sets into our table.
Now that the process of inserting is streamlined, I am supposed to consolidate the existing duplicates in the table.
The table looks like this:
I have 138 of these pairs where the PreOrderNumber occurrs twice. I'd like to insert the FK_VehicleFile number and the CommissionNumber to the row where the FK_Checklist is set and delete the duplicate with the missing FK_Checklist after that.
My idea is to write a transact script that looks like this:
First I store all the PreOrderNumbers that have duplicates in its an own table:
DECLARE #ResultSet TABLE ( PK_OrderNumber int,
FK_Checklist int,
FK_VehicleFile int,
PreOrderNumbers varchar(20))
INSERT INTO #ResultSet
SELECT PK_OrderNumber, PreOrderNumber
FROM [LUX_WEB_SAM].[dbo].[OrderNumbers]
GROUP BY PreOrderNumber
HAVING (COUNT(PreOrderNumber) > 1)
And that's it so far.
I'm very new to these kind of SQL scripts.
I think I need to use some kind of loop over all entries in the #ResultSet table to grab the FK_VehicleFile and CommissionNumber from the first data set and store them in the second data set.
Or do you have and suggestions how to solve this problem in a more easy way?
This response uses a CTE:
WITH [MergedOrders] AS
(
Select
ROW_NUMBER() OVER(PARTITION BY row1.PreOrderNumber ORDER BY row1.PK_OrderNumber) AS Instance
,row1.PK_OrderNumber AS PK_OrderNumber
,ISNULL(row1.FK_Checklist,row2.FK_Checklist) AS FK_Checklist
,ISNULL(row1.FK_VehicleFile,row2.FK_VehicleFile) AS FK_VehicleFile
,ISNULL(row1.PreOrderNumber,row2.PreOrderNumber) AS PreOrderNumber
,ISNULL(row1.CommissionNumber,row2.CommissionNumber) AS CommissionNumber
FROM [LUX_WEB_SAM].[dbo].[OrderNumbers] AS row1
INNER JOIN [LUX_WEB_SAM].[dbo].[OrderNumbers] AS row2
ON row1.PreOrderNumber = row2.PreOrderNumber
AND row1.PK_OrderNumber <> row2.PK_OrderNumber
)
SELECT
[PK_OrderNumber]
,[FK_Checklist]
,[FK_VehicleFile]
,[PreOrderNumber]
,[CommissionNumber]
FROM [MergedOrders]
WHERE Instance = 1 /* If we were to maintain Order Number of second instance, use 2 */
Here's the explanation:
A Common Table Expression (CTE) acts as an in-memory table, which we use to extract all rows that are repeated (NB: The INNER JOIN statement ensures that only rows that occur twice are selected). We use ISNULL to switch out values where one or the other is NULL, then select the output for our destination table.
You can take help from following scripts to perform your UPDATE and DELETE action.
Please keep in mind that both UPDATE and DELETE are risky operation and do your test first with test data.
CREATE TABLE #T(
Col1 VARCHAR(100),
Col2 VARCHAR(100),
Col3 VARCHAR(100),
Col4 VARCHAR(100),
Col5 VARCHAR(100)
)
INSERT INTO #T(Col1,Col2,Col3,Col4,Col5)
VALUES(30,NULL,222,00000002222,096),
(25,163,NULL,00000002222,NULL),
(30,163,NULL,00000002230,NULL)
SELECT * FROM #T
UPDATE A
SET A.Col3 = B.Col3, A.Col5 = B.Col5
FROM #T A
INNER JOIN #T B ON A.Col4 = B.Col4
WHERE A.Col2 IS NOT NULL AND B.Col2 IS NULL
DELETE FROM #T
WHERE Col4 IN (
SELECT Col4 FROM #T
GROUP BY Col4
HAVING COUNT(*) = 2
)
AND Col2 IS NULL
SELECT * FROM #T
I have a query that joins a master and a detail table. Master table records are duplicated in results as expected. I get aggregation on detail table an it works fine. But I also need another aggregation on master table at the same time. But as master table is duplicated, aggregation results are duplicated too.
I want to demonstrate this situation as below;
If Object_Id('tempdb..#data') Is Not Null Drop Table #data
Create Table #data (Id int, GroupId int, Value int)
If Object_Id('tempdb..#groups') Is Not Null Drop Table #groups
Create Table #groups (Id int, Value int)
/* insert groups */
Insert #groups (Id, Value)
Values (1,100), (2,200), (3, 200)
/* insert data */
Insert #data (Id, GroupId, Value)
Values (1,1,10),
(2,1,20),
(3,2,50),
(4,2,60),
(5,2,70),
(6,3,90)
My select query is
Select Sum(data.Value) As Data_Value,
Sum(groups.Value) As Group_Value
From #data data
Inner Join #groups groups On groups.Id = data.GroupId
The result is;
Data_Value Group_Value
300 1000
Expected result is;
Data_Value Group_Value
300 500
Please note that, derived table or sub-query is not an option. Also Sum(Distinct groups.Value) is not suitable for my case.
If I am not wrong, you just want to sum value column of both table and show it in a single row. in that case you don't need to join those just select the sum as a column like :
SELECT (SELECT SUM(VALUE) AS Data_Value FROM #DATA),
(SELECT SUM(VALUE) AS Group_Value FROM #groups)
SELECT
(
Select Sum(d.Value) From #data d
WHERE EXISTS (SELECT 1 FROM #groups WHERE Id = d.GroupId )
) AS Data_Value
,(
SELECT Sum( g.Value) FROM #groups g
WHERE EXISTS (SELECT 1 FROM #data WHERE GroupId = g.Id)
) AS Group_Value
I'm not sure what you are looking for. But it seems like you want the value from one group and the collected value that represents a group in the data table.
In that case I would suggest something like this.
select Sum(t.Data_Value) as Data_Value, Sum(t.Group_Value) as Group_Value
from
(select Sum(data.Value) As Data_Value, groups.Value As Group_Value
from data
inner join groups on groups.Id = data.GroupId
group by groups.Id, groups.Value)
as t
The edit should do the trick for you.
I have a multi statement table valued function which I would like to change to an inline table valued function for optimization purposes ( I don't really know if that will be an optimization but I want to try that anyway ). My problem is that I have a scalar variable which I don't know how to put in my WITH statement.
Code example:
CREATE FUNCTION [dbo].[function]()
RETURNS
#return_table table (id INT,value NVARCHAR(500))
AS
BEGIN
DECLARE #tmp_table TABLE(id INT, value VARCHAR(500))
DECLARE #variable BIGINT
INSERT INTO #tmp_table [...insert code...]
SET #variable = (SELECT MAX(id) FROM #tmp_table)
INSERT INTO #return_table SELECT id,value FROM #tmp_table WHERE id = #variable
RETURN
This code is an example, the actual function is more complex but the problem is exactly the same
I could easily change this to a single WITH statement like this:
CREATE FUNCTION [dbo].[function]()
RETURNS TABLE
AS
RETURN
(
WITH tmp_table AS (
SELECT [...Select Code...]
)
SELECT id,value FROM tmp_table
WHERE id = [variable]
);
GO
My problem lies into the [variable] which I don't know how to put into the query. Also, the variable is used more than once in my function so I'd rather not just replace it with the query.
I also tried this approach:
CREATE FUNCTION [dbo].[function]()
RETURNS TABLE
AS
RETURN
(
WITH tmp_table AS (
SELECT [...Select Code...]
), variable = (SELECT MAX(id) value FROM tmp_table)
SELECT id,value FROM tmp_table
WHERE id = (SELECT TOP 1 value FROM variable)
);
GO
But is seems like it made the function way slower.
Thank you.
Just try
WITH tmp_table AS (
SELECT [...Select Code...]
)
SELECT id,value FROM tmp_table WHERE id = (SELECT MAX(id) FROM tmp_table)
I would actually just change it to
SELECT TOP 1 *
FROm [whatever]
ORDER BY id DESC
I am trying to achieve:
declare #TEMP table (ID int, Name varchar(max))
insert into #temp SELECT ID, Name FROM Table
SELECT * FROM #TEMP
WHERE #TEMP.ID = 1 <--- ERROR AT #TEMP.ID
But I'm getting the following error:
Must declare the scalar variable "#temp".
What am I doing wrong?
A table alias cannot start with a #. So, give #Temp another alias (or leave out the two-part naming altogether):
SELECT *
FROM #TEMP t
WHERE t.ID = 1;
Also, a single equals sign is traditionally used in SQL for a comparison.
Either use an Allias in the table like T and use T.ID, or use just the column name.
declare #TEMP table (ID int, Name varchar(max))
insert into #temp SELECT ID, Name FROM Table
SELECT * FROM #TEMP
WHERE ID = 1
There is one another method of temp table
create table #TempTable (
ID int,
name varchar(max)
)
insert into #TempTable (ID,name)
Select ID,Name
from Table
SELECT *
FROM #TempTable
WHERE ID = 1
Make Sure You are selecting the right database.
If you bracket the # you can use it directly
declare #TEMP table (ID int, Name varchar(max))
insert into #temp values (1,'one'), (2,'two')
SELECT * FROM #TEMP
WHERE [#TEMP].[ID] = 1
You should use hash (#) tables, That you actually looking for because variables value will remain till that execution only.
e.g. -
declare #TEMP table (ID int, Name varchar(max))
insert into #temp SELECT ID, Name FROM Table
When above two and below two statements execute separately.
SELECT * FROM #TEMP
WHERE #TEMP.ID = 1
The error will show because the value of variable lost when you execute the batch of query second time.
It definitely gives o/p when you run an entire block of code.
The hash table is the best possible option for storing and retrieving the temporary value. It last long till the parent session is alive.
try the following query:
SELECT ID,
Name
INTO #tempTable
FROM Table
SELECT *
FROM #tempTable
WHERE ID = 1
It doesn't need to declare table.
You could stil use #TEMP if you quote the identifier "#TEMP":
declare #TEMP table (ID int, Name varchar(max));
insert into #temp SELECT 1 AS ID, 'a' Name;
SELECT * FROM #TEMP WHERE "#TEMP".ID = 1 ;
db<>fiddle demo
You've declared #TEMP but in your insert statement used #temp. Case sensitive variable names.
Change #temp to #TEMP
How can I declare a variable in a table valued function? (like in my title)
There are two flavors of table valued functions. One that is just a select statement and one that can have more rows than just a select statement.
This can not have a variable:
create function Func() returns table
as
return
select 10 as ColName
You have to do like this instead:
create function Func()
returns #T table(ColName int)
as
begin
declare #Var int
set #Var = 10
insert into #T(ColName) values (#Var)
return
end
In SQL Server:
It's not a very nice solution, but if you have a valid reason for needing to use an inline TVF instead of a MSTVF and cannot pass the variable into the TVF as a parameter, but can obtain it using a SELECT statement, you can use a CTE to access the value as follows:
CREATE FUNCTION func()
RETURNS TABLE
AS
RETURN
(
-- Create a CTE table containing just the required value
WITH cte_myVar AS
(SELECT <statement to select variable>) col1
-- Use the value by selecting it from the CTE table
SELECT * FROM table1 t1
WHERE t1.col1 = (SELECT col1 FROM cte_myVar)
)