Updating a table with in clause Error - sql

UPDATE
TABLE1 a,
TABLE2 b
SET
a.COL1 = 'VALUE'
WHERE
a.FK = b.PK
AND b.COL2 IN ('A subquery')
If I am using this update statement and the subquery in the IN clause does not return any rows, I get an error. How do I avoid that? (Oracle 10g)

You likely can rewrite this to an EXISTS query, depending on the exact details of your subquery:
UPDATE TABLE1 a, TABLE2 b SET a.COL1 = 'VALUE'
WHERE a.FK = b.PK AND EXISTS (select 1 from OTHERTABLE O where B.COL2=O.COL2)

UPDATE
TABLE1 a
SET
a.COL1 = 'VALUE'
WHERE
a.FK IN (SELECT b.PK FROM b WHERE b.COL2 in ....)

Is your subquery in quotes?
UPDATE
TABLE1 a,
TABLE2 b
SET
a.COL1 = value
WHERE
a.FK = b.PK
AND b.COL2 IN (
SELECT col2
FROM ...
WHERE ...
)

Related

Updating table with joining to a second table

I'm trying to update the value in column 'ID' from table 1 with the value in column 'ID' from table 2 - Only if they do not match. I think I have everything except the set statement down.
I'm wondering if this is the best way to go about it and how to format the sub-query for this type of problem
update table1 B
set B.id = (select A.id
from table2 A
where B.num = A.num
and B.name = A.name)
where B.num = A.num
and B.name = A.name
and B.id <> A.id
;
Maybe something like this?
update B
set B.id=A.Id
from table1 B
join table2 A
on B.num=A.num
and B.name=A.name
and B.id<>A.id
Oracle does not support join in an update. But you can use two subqueries:
update table1 B
set id = (select A.id
from table2 A
where B.num = A.num and
B.name = A.name
)
where exists (select A.id
from table2 A
where B.num = A.num and
B.name = A.name and
B.id <> A.id
);
Use the MERGE command.
Here is a basic example:
MERGE INTO table1 a
USING (SELECT bb.asdf,cc.zxcv
from table2 bb,table3 cc
where bb.field1=cc.field1) b
ON (a.asdf=b.asdf)
WHEN MATCHED THEN
UPDATE SET a.zxcv=b.zxcv;

Oracle DELETE sql with JOIN doesn't work

My delete statement returns a 933 error in Oracle, I'm not sure what is wrong-
DELETE b
from temp a
JOIN
fact_tab b
on a.col1 = b.col1
and a.col2 = b.col2
and a.col3 = b.col3;
Both tables dont have a primary key. select statement on the same thing works-
select *
from temp a
JOIN
fact_tab b
on a.col1 = b.col1
and a.col2 = b.col2
and a.col3 = b.col3;
try this
DELETE FROM
fact_tab
WHERE
EXISTS
(
SELECT
1
FROM
temp
WHERE
temp.col1 = fact_tab.col1 AND
temp.col2 = fact_tab.col2 AND
temp.col2 = fact_tab.col2
)
Oracle doesn't allow JOIN in a DELETE statement directly like that.
You could do the delete in the following way:
DELETE
FROM fact_tab
WHERE ROWID IN
(SELECT b.rowid
FROM temp a
JOIN fact_tab b
ON a.col1 = b.col1
AND A.col2 = b.col2
AND A.col3 = b.col3
);
You could also use WHERE EXISTS clause.

Netezza UPDATE from one table to another

This is my query that does not work in Netezza:
UPDATE TABLE1 A
SET A.COL1= (SELECT DISTINCT B.COL1 FROM TABLE2 B WHERE B.ID= A.ID AND B.DeptID=104)
WHERE A.DeptID=3
How do I re-write this query?
Please help.
UPDATE TABLE1 A
SET A.COL1 = B.COL1
FROM TABLE2 B
WHERE
A.ID = B.ID AND
A.DeptID = 3 AND
B.DeptID = 104;

update table with join without PK in oracle

UPDATE
(
SELECT
a.COL1
FROM
TABLE1 a,
TABLE2 b,
TABLE3 c
WHERE
a.name = b.name
c.ccol = b.ccol AND
AND b.col1 = 'anyvalue'
AND a.col2 = 'anothervalue'
) u
SET
u.COL1 = 'VALUE'
This query does not work, since TABLE1 does not contains PK. How to write such a query ?
The following should achieve what it looks like you are trying to achieve above:
UPDATE TABLE1
SET COL1 = 'VALUE'
WHERE EXISTS
( SELECT 1
FROM TABLE2 B
INNER JOIN TABLE3 C
ON B.Ccol = C.Ccol
WHERE b.Name = Table1.Name
AND b.Col1 = 'AnyValue'
AND c.Col1 = 'AnotherValue'
)
I've never worked in oracle, but try something like this. Not having a pk shouldn't be an issue, as long as your joins & where statements are correct.
This is the SQL equivalent of what you're asking for
UPDATE u
SET u.COL1 = 'VALUE'
FROM Table1 AS u
INNER JOIN Table2 AS b ON u.name = b.name
INNER JOIN Table3 AS c ON c.ccol = b.ccol
WHERE b.col1 = 'anyvalue' AND u.col2 = 'anothervalue'

How to delete rows from tables which is referenced each other?

I want to do this:
delete from table1 a,table2 b, table3 c
where a.col1 = b.col1
and b.col2 = c.col2
and a.co3 <> 8001;
But its giving me an error.
delete the lowest level first and move up from there, one delete per level, to the highest level:
DELETE FROM ChildTable WHERE ParentID=...
DELECT FROM ParentTable WHERE ParentID=...
You could turn cascade deletes on then delete the parent record.
Since you did not specify to what each table has a foreign key and on which field, I'll take a guess:
Delete TableC
Where Exists( Select 1 From TableA Where TableA.Col1 = TableC.Col2 And TableA.Col3 <> '8001' )
Delete TableB
Where Exists( Select 1 From TableA Where TableA.Col1 = TableB.Col2 And TableA.Col3 <> '8001' )
Delete TableA
Where Col3 <> '8001'
delete A from table1 a,table2 b, table3 c
where a.col1 = b.col1
and b.col2 = c.col2
and a.co3 <> 8001;