I have a straight forward SQL query that I am working with and trying to figure out the best way to approach the where clause.
Essentially, there are two temp tables created and if there is data in the XML string passed to the stored procedure, those tables are populated.
My where clause needs to check these temp tables for data, and if there is no data, it ignores them like they are not there and fetches all data.
-- Create temp tables to hold our XML filter criteria
DECLARE #users AS TABLE (QID VARCHAR(10))
DECLARE #dls AS TABLE (dlName VARCHAR(50))
-- Insert our XML filters
IF #xml.exist('/root/data/users') > 0
BEGIN
INSERT INTO #users( QID )
SELECT ParamValues.x1.value('QID[1]', 'varchar(10)')
FROM #xml.nodes('/root/data/users/user') AS ParamValues(x1)
END
IF #xml.exist('/root/data/dls') > 0
BEGIN
INSERT INTO #dls( dlName )
SELECT ParamValues.x1.value('dlName[1]', 'varchar(50)')
FROM #xml.nodes('/root/data/dld/dl') AS ParamValues(x1)
END
-- Fetch our document details based on the XML provided
SELECT d.documentID ,
d.sopID ,
d.documentName ,
d.folderLocation ,
d.userGroup ,
d.notes
FROM dbo.Documents AS d
LEFT JOIN dbo.DocumentContacts AS dc
ON dc.documentID = d.documentID
LEFT JOIN dbo.DocumentContactsDLs AS dl
ON dl.documentID = d.documentID
-- How can I make these two logic checks work only if there is data, otherwise, include everything.
WHERE dc.QID IN (SELECT QID FROM #users)
AND dl.DL IN (SELECT dlName FROM #dls)
FOR XML PATH ('data'), ELEMENTS, TYPE, ROOT('root');
In the query above, I am trying to used the data in the temp tables only if there is data in them, otherwise, it needs to act like that where statement isn't there for that specific value and include records regardless.
Example: If only #users had data, it would ignore AND dl.DL IN (SELECT dlName FROM #dls) and get everything, regardless of what was in the DL column on those joined records.
Use NOT EXISTS to check the existence of any record in variable table. Here is one way
WHERE ( dc.QID IN (SELECT QID FROM #users)
OR NOT EXISTS (SELECT 1 FROM #users) )
AND ( dl.DL IN (SELECT dlName FROM #dls)
OR NOT EXISTS (SELECT 1 FROM #dls) )
Try this. But please note that I did not get a chance to test it properly and I believe that you want to check the values in #users first and if there is no record existing in that table, then you want to check with the entries in #dls. Also if there are no entries in both of these tables, then you want to skip both the tables.
DECLARE #fl bit = 0
SELECT #fl = CASE WHEN EXISTS (SELECT 1 FROM #users) THEN
1
WHEN EXISTS (SELECT 1 FROM #dls) THEN
2
ELSE
0
END
WHERE ( (dc.QID IN (SELECT QID FROM #users) AND #fl = 1)
OR
(dl.DL IN (SELECT dlName FROM #dls) AND #fl = 2)
OR (1=1 AND #fl = 0)
)
Related
I have a table [Order] that has records with sequential ID (in odd number only, i.e. 1,3,5,7...989, 991, 993, 995, 997, 999), it is seen that a few records were accidentally deleted and should be inserted back, first thing is to find out what records are missing in the current table, there are hundreds of records in this table
Don't know how to write the query, can anyone kindly help, please?
I am thinking if I have to write a stored procedure or function but would be better if I can avoid them for environment reasons.
Below peuso code is what I am thinking:
set #MaxValue = Max(numberfield)
set #TestValue = 1
open cursor on recordset ordered by numberfield
foreach numberfield
while (numberfield != #testvalue) and (#testvalue < #MaxValue) then
Insert #testvalue into #temp table
set #testvalue = #textvalue + 2
Next
Next
UPDATE:
Expected result:
Order ID = 7 should be picked up as the only missing record.
Update 2:
If I use
WHERE
o.id IS NULL;
It returns nothing:
Since I didn't get a response from you, in the comments, I've altered the script for you to fill in accordingly:
declare #id int
declare #maxid int
set #id = 1
select #maxid = max([Your ID Column Name]) from [Your Table Name]
declare #IDseq table (id int)
while #id < #maxid --whatever you max is
begin
insert into #IDseq values(#id)
set #id = #id + 1
end
select
s.id
from #IDseq s
left join [Your Table Name] t on s.id = t.[Your ID Column Name]
where t.[Your ID Column Name] is null
Where you see [Your ID Column Name], replace everything with your column name and the same goes for [Your Table Name].
I'm sure this will give you the results you seek.
We can try joining to a number table, which contains all the odd numbers which you might expect to appear in your own table.
DECLARE #start int = 1
DECLARE #end int = 1000
WITH cte AS (
SELECT #start num
UNION ALL
SELECT num + 2 FROM cte WHERE num < #end
)
SELECT num
FROM cte t
LEFT JOIN [Order] o
ON t.num = o.numberfield
WHERE
o.numberfield IS NULL;
I have a set of records that need to be validated (searched) in a SQL table. I will call these ValData and SearchTable respectively. A colleague created a SQL query in which a record from the ValData can be copied and pasted in to a string variable, and then it is searched in the SearchTable. The best result from the SearchTable is returned. This works very well.
I want to automate this process. I loaded the ValData to SQL in a table like so:
RowID INT, FirstName, LastName, DOB, Date1, Date2, TextDescription.
I want to loop through this set of data, by RowID, and then create a result table that is the ValData joined with the best match from the SearchTable. Again, I already have a query that does that portion. I just need the loop portion, and my SQL skills are virtually non-existent.
Suedo code would be:
DECLARE #SearchID INT = 1
DECLARE #MaxSearchID INT = 15000
DECLARE #FName VARCHAR(50) = ''
DECLARE #FName VARCHAR(50) = ''
etc...
WHILE #SearchID <= #MaxSearchID
BEGIN
SET #FNAME = (SELECT [Fname] FROM ValData WHERE [RowID] = #SearchID)
SET #LNAME = (SELECT [Lname] FROM ValData WHERE [RowID] = #SearchID)
etc...
Do colleague's query, and then insert(?) search criteria joined with the result from the SearchTable in to a temporary result table.
END
SELECT * FROM FinalResultTable;
My biggest lack of knowledge comes in how do I create a temporary result table that is ValData's fields + SearchTable's fields, and during the loop iterations how do I add one row at a time to this temporary result table that includes the ValData joined with the result from the SearchTable?
If it helps, I'm using/wanting to join all fields from ValData and all fields from SearchTable.
Wouldn't this be far easier with a query like this..?
SELECT FNAME,
LNAME
FROM ValData
WHERE (FName = #Fname
OR LName = #Lname)
AND RowID <= #MaxSearchID
ORDER BY RowID ASC;
There is literally no reason to use a WHILE other than to destroy performance of the query.
With a bit more trial and error, I was able to answer what I was looking for (which, at its core, was creating a temp table and then inserting rows in to it).
CREATE TABLE #RESULTTABLE(
[feedname] VARCHAR(100),
...
[SCORE] INT,
[Max Score] INT,
[% Score] FLOAT(4),
[RowID] SMALLINT
)
SET #SearchID = 1
SET #MaxSearchID = (SELECT MAX([RowID]) FROM ValidationData
WHILE #SearchID <= #MaxSearchID
BEGIN
SET #FNAME = (SELECT [Fname] FROM ValidationData WHERE [RowID] = #SearchID)
...
--BEST MATCH QUERY HERE
--Select the "top" best match (order not guaranteed) in to the RESULTTABLE.
INSERT INTO #RESULTTABLE
SELECT TOP 1 *, #SearchID AS RowID
--INTO #RESULTTABLE
FROM #TABLE3
WHERE [% Score] IN (SELECT MAX([% Score]) FROM #TABLE3)
--Drop temp tables that were created/used during best match query.
DROP TABLE #TABLE1
DROP TABLE #TABLE2
DROP TABLE #TABLE3
SET #SearchID = #SearchID + 1
END;
--Join the data that was validated (searched) to the results that were found.
SELECT *
FROM ValidationData vd
LEFT JOIN #RESULTTABLE rt ON rt.[RowID] = vd.[RowID]
ORDER BY vd.[RowID]
DROP TABLE #RESULTTABLE
I know this could be approved by doing a join, probably with the "BEST MATCH QUERY" as an inner query. I am just not that skilled yet. This takes a manual process which took hours upon hours and shortens it to just an hour or so.
The Situation
We have an application where we store machine settings in a SQL table. When the user changes a parameter of the machine, we create a "revision", that means we insert a row into a table. This table has about 200 columns.
In our application, the user can take a look on each revision.
The Problem
We want to highlight the parameters that have changed since the last revision.
The Question
Is there an SQL-only way to get the column names of the differences between two rows?
An Example
ID | p_x | p_y | p_z
--------------------
11 | xxx | yyy | zzz
12 | xxy | yyy | zzy
The query should return p_x and p_z.
EDIT
The table has 200 columns, not rows...
MY WAY OUT
My intention was to find a "one-line-SQL-statement" for this problem.
I see in the answers below, it's kind a bigger thing in SQL.
As there is no short, SQL-included solution for this problem, solving it in the backend of our software (c#) is of course much easier!
But as this is not a real "answer" to my question, I don't mark it as answered.
Thanks for the help.
You say:
We want to highlight the parameters that have changed since the last revision.
This implies that you want the display (or report) to make the parameters that changed stand out.
If you're going to show all the parameters anyway, it would be a lot easier to do this programmatically in the front end. It would be a much simpler problem in a programming language. Unfortunately, not knowing what your front end is, I can't give you particular recommendations.
If you really can't do it in the front end but have to receive this information in a query from the database (you did say "SQL-only"), you need to specify the format you'd like the data in. A single-column list of the columns that changed between the two records? A list of columns with a flag indicating which columns did or didn't change?
But here's one way that would work, though in the process it converts all your fields to nvarchars before it does its comparison:
Use the technique described here (disclaimer: that's my blog) to transform your records into ID-name-value pairs.
Join the resulting data set to itself on ID, so that you can compare the values and print those that have changed:
with A as (
-- We're going to return the product ID, plus an XML version of the
-- entire record.
select ID
, (
Select *
from myTable
where ID = pp.ID
for xml auto, type) as X
from myTable pp )
, B as (
-- We're going to run an Xml query against the XML field, and transform it
-- into a series of name-value pairs. But X2 will still be a single XML
-- field, associated with this ID.
select Id
, X.query(
'for $f in myTable/#*
return
<data name="{ local-name($f) }" value="{ data($f) }" />
')
as X2 from A
)
, C as (
-- We're going to run the Nodes function against the X2 field, splitting
-- our list of "data" elements into individual nodes. We will then use
-- the Value function to extract the name and value.
select B.ID as ID
, norm.data.value('#name', 'nvarchar(max)') as Name
, norm.data.value('#value', 'nvarchar(max)') as Value
from B cross apply B.X2.nodes('/myTable') as norm(data))
-- Select our results.
select *
from ( select * from C where ID = 123) C1
full outer join ( select * from C where ID = 345) C2
on C1.Name = c2.Name
where c1.Value <> c2.Value
or not (c1.Value is null and c2.Value is null)
You can use unpivot and pivot. The key is to transpose data so that you can use where [11] != [12].
WITH CTE AS (
SELECT *
FROM
(
SELECT ID, colName, val
FROM tblName
UNPIVOT
(
val
FOR colName IN ([p_x],[p_y],[p_z])
) unpiv
) src
PIVOT
(
MAX(val)
FOR ID IN ([11], [12])
) piv
)
SELECT colName
--SELECT *
FROM CTE WHERE [11] != [12]
If there are only a few columns in the table, it's easy to simply put [p_x],[p_y],[p_z], but obviously it's not convenient to type 50 or more columns. Even though you may use this trick to drag and drop, or copy/paste, the column names from the table, it's still bulky. And for that, you may use the SELECT * EXCEPT strategy with dynamic sql.
DECLARE #TSQL NVARCHAR(MAX), #colNames NVARCHAR(MAX)
SELECT #colNames = COALESCE(#colNames + ',' ,'') + [name]
FROM syscolumns WHERE name <> 'ID' and id = (SELECT id FROM sysobjects WHERE name = 'tablelName')
SET #TSQL = '
WITH CTE AS (
SELECT *
FROM
(
SELECT ID, colName, val
FROM tablelName
UNPIVOT
(
val
FOR colName IN (' + #colNames + ')
) unpiv
) src
PIVOT
(
MAX(val)
FOR ID IN ([11], [12])
) piv
)
--SELECT colName
SELECT *
FROM CTE WHERE [11] != [12]
'
EXEC sp_executesql #TSQL
Here's one way using UNPIVOT:
;WITH
cte AS
(
SELECT CASE WHEN t1.p_x <> t2.p_x THEN 1 ELSE 0 END As p_x,
CASE WHEN t1.p_y <> t2.p_y THEN 1 ELSE 0 END As p_y,
CASE WHEN t1.p_z <> t2.p_z THEN 1 ELSE 0 END As p_z
FROM MyTable t1, MyTable t2
WHERE t1.ID = 11 AND t2.ID = 12 -- enter the two revisions to compare here
)
SELECT *
FROM cte
UNPIVOT (
Changed FOR ColumnName IN (p_x, p_y, p_z)
) upvt
WHERE upvt.Changed = 1
You have to add code to handle NULLs during the comparisons. You can also build the query dynamically if there are lots of columns in your table.
for sql server 2012 you can do something like that (duplicate it for
each column):
SELECT iif((p_x != lead(p_x) over(ORDER BY p_x)),
(SELECT COLUMN_NAME
FROM INFORMATION_SCHEMA.COLUMNS
WHERE TABLE_NAME = 'tbl'
AND
TABLE_SCHEMA='schema'
AND
ORDINAL_POSITION='1')
,NULL)
FROM tbl
for sql server 2008 try
DECLARE #x int =11 -- first id
WHILE #x!=(SELECT count(1) FROM tbl)
BEGIN --comparison of two adjacent rows
if (SELECT p_x FROM tbl WHERE id=#x)!=(SELECT p_x FROM tbl WHERE id=#x+1)
BEGIN
SELECT COLUMN_NAME
FROM INFORMATION_SCHEMA.COLUMNS
WHERE TABLE_NAME = 'tbl' --insert your table
AND
TABLE_SCHEMA='schema' --insert your schema
AND
ORDINAL_POSITION='1' --first column 'p_x'
END
set #x=#x+1
END
I have a need to monitor a subset of fields on a table and perform a task when one of them changes.
I am using a trigger on the table update which and then am looking at the changes as follows:
-- join the deleted and inserted to get a full list of rows
select * into #tmp from (select * from inserted union select * from deleted) un
-- select a count of differing rows, > 1 means something is different
select distinct count(*) from #tmp
This is fine and a count of 2 or more means something is different on single line updates. Issue is if I am doing a multiple line update then this breaks down.
Is there a way I can get this to work for a multi line update or do I need to try a different approach completely.
You could do something like this (syntax completely untested)
IF NOT UPDATE(col)
RETURN
SELECT inserted.key, inserted.col as i_col, deleted.col as d_col
INTO #interestingrows
FROM inserted JOIN deleted on inserted.key = deleted.key
and inserted.col <> deleted.col /*If col is nullable cater for that as well*/
IF ##ROWCOUNT=0
RETURN
/*Process contents of #interestingrows*/
I ended up with a fairly simple solution. I wrote an additional loop around the check that did the check per line in inserted.
-- get a list of updated line id's
select field1 as id into #loop from inserted
-- loop through all the id's and do a compare
while (select count(*) from #loop) > 0 begin
select top 1 #id = id from #loop
select * into #tmp from (select * from inserted where field1 = #id union
select * from deleted where field1 = #id) un
-- do a select ditinct to count the differing lines.
if (select distinct count(*) from #tmp) > 1 begin
-- the 2 lines don't match, so mark for update
update test1 set flag = 1 where field1 = #id
end
drop table #tmp
delete #loop where id = #id
end
I would like to know if there is a way to use an order by clause when updating a table. I am updating a table and setting a consecutive number, that's why the order of the update is important. Using the following sql statement, I was able to solve it without using a cursor:
DECLARE #Number INT = 0
UPDATE Test
SET #Number = Number = #Number +1
now what I'd like to to do is an order by clause like so:
DECLARE #Number INT = 0
UPDATE Test
SET #Number = Number = #Number +1
ORDER BY Test.Id DESC
I've read: How to update and order by using ms sql The solutions to this question do not solve the ordering problem - they just filter the items on which the update is applied.
Take care,
Martin
No.
Not a documented 100% supported way. There is an approach sometimes used for calculating running totals called "quirky update" that suggests that it might update in order of clustered index if certain conditions are met but as far as I know this relies completely on empirical observation rather than any guarantee.
But what version of SQL Server are you on? If SQL2005+ you might be able to do something with row_number and a CTE (You can update the CTE)
With cte As
(
SELECT id,Number,
ROW_NUMBER() OVER (ORDER BY id DESC) AS RN
FROM Test
)
UPDATE cte SET Number=RN
You can not use ORDER BY as part of the UPDATE statement (you can use in sub-selects that are part of the update).
UPDATE Test
SET Number = rowNumber
FROM Test
INNER JOIN
(SELECT ID, row_number() OVER (ORDER BY ID DESC) as rowNumber
FROM Test) drRowNumbers ON drRowNumbers.ID = Test.ID
Edit
Following solution could have problems with clustered indexes involved as mentioned here. Thanks to Martin for pointing this out.
The answer is kept to educate those (like me) who don't know all side-effects or ins and outs of SQL Server.
Expanding on the answer gaven by Quassnoi in your link, following works
DECLARE #Test TABLE (Number INTEGER, AText VARCHAR(2), ID INTEGER)
DECLARE #Number INT
INSERT INTO #Test VALUES (1, 'A', 1)
INSERT INTO #Test VALUES (2, 'B', 2)
INSERT INTO #Test VALUES (1, 'E', 5)
INSERT INTO #Test VALUES (3, 'C', 3)
INSERT INTO #Test VALUES (2, 'D', 4)
SET #Number = 0
;WITH q AS (
SELECT TOP 1000000 *
FROM #Test
ORDER BY
ID
)
UPDATE q
SET #Number = Number = #Number + 1
The row_number() function would be the best approach to this problem.
UPDATE T
SET T.Number = R.rowNum
FROM Test T
JOIN (
SELECT T2.id,row_number() over (order by T2.Id desc) rowNum from Test T2
) R on T.id=R.id
update based on Ordering by the order of values in a SQL IN() clause
Solution:
DECLARE #counter int
SET #counter = 0
;WITH q AS
(
select * from Products WHERE ID in (SELECT TOP (10) ID FROM Products WHERE ID IN( 3,2,1)
ORDER BY ID DESC)
)
update q set Display= #counter, #counter = #counter + 1
This updates based on descending 3,2,1
Hope helps someone.
I had a similar problem and solved it using ROW_NUMBER() in combination with the OVER keyword. The task was to retrospectively populate a new TicketNo (integer) field in a simple table based on the original CreatedDate, and grouped by ModuleId - so that ticket numbers started at 1 within each Module group and incremented by date. The table already had a TicketID primary key (a GUID).
Here's the SQL:
UPDATE Tickets SET TicketNo=T2.RowNo
FROM Tickets
INNER JOIN
(select TicketID, TicketNo,
ROW_NUMBER() OVER (PARTITION BY ModuleId ORDER BY DateCreated) AS RowNo from Tickets)
AS T2 ON T2.TicketID = Tickets.TicketID
Worked a treat!
I ran into the same problem and was able to resolve it in very powerful way that allows unlimited sorting possibilities.
I created a View using (saving) 2 sort orders (*explanation on how to do so below).
After that I simply applied the update queries to the View created and it worked great.
Here are the 2 queries I used on the view:
1st Query:
Update MyView
Set SortID=0
2nd Query:
DECLARE #sortID int
SET #sortID = 0
UPDATE MyView
SET #sortID = sortID = #sortID + 1
*To be able to save the sorting on the View I put TOP into the SELECT statement. This very useful workaround allows the View results to be returned sorted as set when the View was created when the View is opened. In my case it looked like:
(NOTE: Using this workaround will place an big load on the server if using a large table and it is therefore recommended to include as few fields as possible in the view if working with large tables)
SELECT TOP (600000)
dbo.Items.ID, dbo.Items.Code, dbo.Items.SortID, dbo.Supplier.Date,
dbo.Supplier.Code AS Expr1
FROM dbo.Items INNER JOIN
dbo.Supplier ON dbo.Items.SupplierCode = dbo.Supplier.Code
ORDER BY dbo.Supplier.Date, dbo.Items.ID DESC
Running: SQL Server 2005 on a Windows Server 2003
Additional Keywords: How to Update a SQL column with Ascending or Descending Numbers - Numeric Values / how to set order in SQL update statement / how to save order by in sql view / increment sql update / auto autoincrement sql update / create sql field with ascending numbers
SET #pos := 0;
UPDATE TABLE_NAME SET Roll_No = ( SELECT #pos := #pos + 1 ) ORDER BY First_Name ASC;
In the above example query simply update the student Roll_No column depending on the student Frist_Name column. From 1 to No_of_records in the table. I hope it's clear now.
IF OBJECT_ID('tempdb..#TAB') IS NOT NULL
BEGIN
DROP TABLE #TAB
END
CREATE TABLE #TAB(CH1 INT,CH2 INT,CH3 INT)
DECLARE #CH2 INT = NULL , #CH3 INT=NULL,#SPID INT=NULL,#SQL NVARCHAR(4000)='', #ParmDefinition NVARCHAR(50)= '',
#RET_MESSAGE AS VARCHAR(8000)='',#RET_ERROR INT=0
SET #ParmDefinition='#SPID INT,#CH2 INT OUTPUT,#CH3 INT OUTPUT'
SET #SQL='UPDATE T
SET CH1=#SPID,#CH2= T.CH2,#CH3= T.CH3
FROM #TAB T WITH(ROWLOCK)
INNER JOIN (
SELECT TOP(1) CH1,CH2,CH3
FROM
#TAB WITH(NOLOCK)
WHERE CH1 IS NULL
ORDER BY CH2 DESC) V ON T.CH2= V.CH2 AND T.CH3= V.CH3'
INSERT INTO #TAB
(CH2 ,CH3 )
SELECT 1,2 UNION ALL
SELECT 2,3 UNION ALL
SELECT 3,4
BEGIN TRY
WHILE EXISTS(SELECT TOP 1 1 FROM #TAB WHERE CH1 IS NULL)
BEGIN
EXECUTE #RET_ERROR = sp_executesql #SQL, #ParmDefinition,#SPID =##SPID, #CH2=#CH2 OUTPUT,#CH3=#CH3 OUTPUT;
SELECT * FROM #TAB
SELECT #CH2,#CH3
END
END TRY
BEGIN CATCH
SET #RET_ERROR=ERROR_NUMBER()
SET #RET_MESSAGE = '#ERROR_NUMBER : ' + CAST(ERROR_NUMBER() AS VARCHAR(255)) + '#ERROR_SEVERITY :' + CAST( ERROR_SEVERITY() AS VARCHAR(255))
+ '#ERROR_STATE :' + CAST(ERROR_STATE() AS VARCHAR(255)) + '#ERROR_LINE :' + CAST( ERROR_LINE() AS VARCHAR(255))
+ '#ERROR_MESSAGE :' + ERROR_MESSAGE() ;
SELECT #RET_ERROR,#RET_MESSAGE;
END CATCH