I have got two table
create table t1(cid int, isnews int)
create table t2(nid int,cid int, isnews int)
situations is like this:
if t2 contain t2.cid = t1.cid then the t2.isnews = t1.news and
if t2 not contain cid of t1 then new record should be inserted in t2 and that t1.cid, t1.isnews should be inserted in t2..
and complete table should be done in single query... i have done the updation part but not able to do insertion part..
update query:
UPDATE t22
SET t22.isnews = t11.isnews
FROM t2 AS t22
JOIN t1 AS t11
ON t11.cid= t22.cid
i have prepared below cursor for insert... is it good? :
DECLARE #clntid INT
DECLARE #clntnewsltr INT
DECLARE clientnews CURSOR FOR
SELECT clientid,newsLetter
FROM clients
WHERE clientid NOT IN (SELECT clientid FROM clientprivacy)
OPEN clientnews
FETCH NEXT FROM clientnews INTO #clntid,#clntnewsltr
WHILE ##FETCH_STATUS = 0
BEGIN
INSERT INTO clientprivacy (clientId,tdNewsLetters) VALUES(#clntid, #clntnewsltr)
FETCH NEXT FROM clientnews INTO #clntid,#clntnewsltr
END
CLOSE clientnews
DEALLOCATE clientnews
I think this is the kind of thing you're after:
--INSERT t2 (cid, isnews)
SELECT t1.cid, t1.isnews
FROM t1
LEFT JOIN t2 ON t1.cid = t2.cid
WHERE t2.cid IS NULL
I've commented out the INSERT line - I recommend you run the SELECT on it's own first to check it does give you the correct result (all records from t1 that don't have a matching cid in t2).
I've assumed t2.nid is an IDENTITY column.
You will be so much better off without cursors :) Cursors take MUCH longer to run in large data sets.
It is true you can use a LEFT JOIN, but you can also use a SELECT in your WHERE clause. Most of the time it's a style choice.
CREATE TABLE table1(col_1 int, col_2 int)
CREATE TABLE table2(nid int, col_1 int, col_2 int)
INSERT INTO table2 (col_1,col_2)
SELECT col_1,col_2
FROM table1
WHERE col_1 NOT IN (SELECT col_1 FROM table2)
Related
This might be a stupid question, but I am not a DBA and kind of stuck with this issue. I have an application that trickles down all effects (asdf) under an applied ID (IDParent).
The data tables are setup like this:
Data Tables
3rd Data Table
I want to write a query that when using IDChild it will reference that entry's IDParent to get the parent ID while referencing it as an IDChild. For example for the data entry starting at 116 I want to use the parent ID (124) and get 321 in T1. I want to use this to get the RandoName associated with RandoID for all of the entries that has a parent ID of 321.
Right now I am using a script something like:
Select t.[NAME]
From T2 tv
Inner join T3 t on t.RandoID = tv.RandoId
Where
tv.IDChild = T1.IDChild OR tv.IDChild = T1.IDParent
but I'm not sure how to get the whole applied hierarchy.
This would yield something like this:
Resulting Query
PS. I can not change the tables/db schema. But maybe I can add one to do all the referencing? Please tell me what you think.
EDIT I'm sorry I forgot about this other stupid table that RandoID uses which contains the name of the RandoID. I am trying to get the name of RandoID
I think a loop could help you.
Try this:
CREATE TABLE #t1 (IDChild Int, IDParent Int);
CREATE TABLE #t2 (RandoID NVARCHAR(10) , IDChild Int);
CREATE TABLE #RandoName (RandoID NVARCHAR(10), RandoName VARCHAR(50));
INSERT INTO #t1 VALUES (321, NULL), (123,321),(124,123),(116,124)
INSERT INTO #t2 VALUES ('asdf', 123)
INSERT INTO #RandoName VALUES ('asdf', 'something')
SELECT ROW_NUMBER() OVER (ORDER BY (SELECT 100)) [RowNum], a.IDChild a, a.IDParent b, b.IDChild c INTO #t3 FROM #t1 a
LEFT OUTER JOIN #t1 b ON b.IDParent = a.IDChild
DECLARE #rownum INT;
DECLARE cbcursor CURSOR for Select RowNum FROM #t3;
OPEN cbcursor;
Fetch Next from cbcursor into #rownum
WHILE ##FETCH_STATUS = 0
BEGIN
UPDATE #t3
SET c = (SELECT b from #t3 where RowNum = #rownum-1)
WHERE RowNum = #rownum
Fetch Next from cbcursor into #rownum;
END;
Close cbcursor;
Deallocate cbcursor;
SELECT a,b,t2.RandoID, r.RandoName FROM #t3
LEFT OUTER JOIN #t2 t2 on t2.IDChild = #t3.c OR t2.IDChild = #t3.b OR t2.IDChild = #t3.a
LEFT OUTER JOIN #RandoName r on t2.RandoID = r.RandoID
This is what I get:
If you have any changes in your tables, like more records for T2, this script should be modified.
Using recursion:
declare #t table (IDc int , Idp int)
insert into #t
values
(321,null)
,(123,321)
,(124,123)
,(116,124)
declare #t2 table (RandoID varchar(10), IDChild int)
insert into #t2
values('asdf',123)
;with cte as
(
select anchor = IDChild
,ParentOrSelf = IDc
,RandoID
,RandomName
from #t
cross join (select RandoID,RandoName from #t2 t2 join #t3 t3 on t2.RandoID=t3.RandoID) crossed
where IDc=#anchor
union all
select t2.IDChild
,IDc
, t2.RandoID,RandomName
from #t t
cross join (select RandoID,RandoName from #t2 t2 join #t3 t3 on t2.RandoID=t3.RandoID) t2
join cte on cte.ParentOrSelf = t.Idp
)
select IDc
, cte.RandoID,cte.RandomName
from #t t
left join cte on t.IDc = cte.ParentOrSelf
Results:
IDc RandoID
321 NULL
123 asdf
124 asdf
116 asdf
I want to update each row of table1->keyField based on table2 value
Table1
Id|keyField
1|test_500
2|test_501
3|test_501
500,501 are primary key of and my another table2
Table2
Id|value
500|A
501|B
502|C
I have tried something like
update table1 set keyField=(select value from table2 where id=substring(expression))
but my select return multiple statement so unable to run the query.
any help or direction please?
You can use the syntax like this
UPDATE table1 SET keyField = Table2.Value
FROM table1 INNER JOIN table2
ON table1.Id = substring(expression))
If I get it right, this might be what you need:
UPDATE T1 SET
keyField = T2.Value
FROM
Table1 AS T1
INNER JOIN Table2 AS T2 ON T2.id = SUBSTRING(T1.keyField, 6, 100)
Careful when comparing substring result with an numeric value, might get a conversion error.
Try this code (necessary notes are in comments below):
--generate some sample data (the same as you provided)
declare #table1 table (id int, keyField varchar(10))
insert into #table1 values (1,'test_500'),(2,'test_501'),(3,'test_502')
declare #table2 table (id int, value char(1))
insert into #table2 values (500,'A'),(501,'B'),(502,'C')
--in case you want to see tables first
--select * from #table1
--select * from #table2
--here you extract the number in first table in keyField column and match it with ID from second table, upon that, you update first table
update #table1 set keyField = value from #table2 [t2]
where cast(right(keyfield, len(keyfield) - charindex('_',keyfield)) as int) = [t2].id
select * from #table1
I have join two tables t1 and t2. The output produces some null records since there is no data in the table t2. Instead of showing null I want to show 0 since I have to perform some arithmetic operation in the crystal reports.
please help me.....
sample example
declare #t table (ID int)
declare #t1 table (ID int)
insert into #t (id) values (1)
select t.ID,ISNULL(TT.ID,0)id from #t t
LEFT JOIN #t1 tt
ON t.ID = tt.ID
Use the COALESCE function which automatically replace null values as 0.
Sample
SELECT COALESCE(total_amount, 0) from #Temp1
My Requirement
Updating Values of a table from same table without using a select query
this query won't effect any rows.
My aim : Update val2 of #table where slno=1 with the value of val2 of slno=2
Is there any other way without doing this method
Declare #val2 nvarchar(50)
select #val2=val2 from #table where slno=2
update #table set val2=#val2 where slno=1
create table #table
(
slno int identity(1,1),
val nvarchar(50),
val2 nvarchar(50)
)
insert into #table(val,val2)values('1',newID())
insert into #table(val,val2)values('1',newID())
insert into #table(val,val2)values('1',newID())
select * from #table
update #table set val2=T.val2
from #table T where slno=1 and T.slno=2
drop table #table
I have lot of records in the table.
So If i am selecting and update it may effect the performance.
Please, provide more info.
Do you have only 2 rows in your table?
Why do you need this kind of update?
I suppose, that your db structure is wrong, but I can't tell exactly, until you explain why do you need this.
Anyway I can suggest a poor way to do this without using select. You can self join the table. It would be better to have addition column, but if you don't have it, how's you should do
UPDATE T1
SET T1.val2 = T2.val2
FROM #table T1 INNER JOIN #table T2
ON T1.slno = 1 AND T2.slno = 2
I tried to perform the following in order to update a psuedo-identity value at the same time as using the value to create new rows, but APPLY does not like UPDATE statements as the right table source. What's the most elegant alternative outside of simply using an identity column?
create table Temp1(
id int not null identity(1,1) primary key
,data nvarchar(max) null)
create table Temp2(
id int not null primary key
,fkTemp1 int not null references Temp1(id)
,data nvarchar(max) null)
create table Numbering(
ObjectCode int not null primary key
,AutoKey int)
insert into Temp1(data) values('test string')
insert into Temp1(data) values('another test string')
insert into Numbering(ObjectCode, AutoKey) values(4, 1)
insert into Temp2(id, fkTemp1, data)
select n.AutoKey, t1.id, t1.data
from Temp1 t1
left join Temp2 t2 on t2.fkTemp1 = t1.id
cross apply (update Numbering set AutoKey = AutoKey + 1 output inserted.AutoKey where ObjectCode = 4) n
where t2.id is null -- only insert where a target row does not already exist
You cannot do an INSERT and UPDATE on two different tables in one statement in SQL Server 2005.
In SQL Server 2008 there is MERGE construct, however, it works only on single table.
Just run two statements in a transaction:
BEGIN TRANSACTION
DECLARE #AutoKey INT
SELECT #AutoKey = AutoKey
FROM Numbering WITH (UPDLOCK)
WHERE ObjectCode = 4
INSERT
INTO temp2
SELECT #AutoKey + ROW_NUMBER() OVER (ORDER BY id), id, data
FROM temp1
WHERE id NOT IN
(
SELECT fkTemp1
FROM temp2
)
UPDATE Numbering
SET AutoKey = AutoKey + ##ROWCOUNT
WHERE ObjectCode = 4
COMMIT
Update:
As #Remus Rusanu pointed out, you actually can pipeline UPDATE output clause into a table in SQL Server 2005.
However, it seems you can neither JOIN nor CROSS APPLY the OUTPUT resultset to the result of other queries.
This will do it, but you'll have to fix the "T2.ID IS NULL" problem...
Declare #Key as int
Declare #cnt as int
Begin Transaction
Set #cnt = (Select count(*)
from Temp1 t1 left join Temp2 t2 on t2.fkTemp1 = t1.id
--where t2.id is null -- note: does not work, not sure what is intended
)
update Numbering set #Key = AutoKey = AutoKey + #cnt where ObjectCode = 4
insert into Temp2(id, fkTemp1, data)
select #Key+ROW_NUMBER() over (Order By t1.id)
, t1.id, t1.data
from Temp1 t1
left join Temp2 t2 on t2.fkTemp1 = t1.id
--where t2.id is null -- note: does not work,
Commit Transaction