say I have three tables: TableA, TableB, and TableC. Each of these tables have a column: ColA.
TableA is my main table and TableA.ColA has a value.
I wish to check either TableB or TableC has also a value in their ColA that corresponds with my TableA.ColA.
So my statement is:
select count(*)
from TableA, TableB, TableC
where ( TableA.ColA = TableB.ColA AND TableA.ColA = "ABC")
OR ( TableA.ColA = TableC.ColA AND TableA.ColA = "ABC" )
But this does not work.
If my TableB.ColA doesn't have a ColA value and TableC.ColA has a value, the result returned is still 0. I should get a count of 1 back.
What is wrong with my select statement?
My TableA data:
ColA
-----
ABC
My TableB data:
ColA
----
NULL
My TableC data:
ColA
----
ABC
Because TableC.ColA and TableA.ColA has the same value, it should return me a count of 1. But it is not doing so. My database is SAP ASE
thanks
You are doing INNER JOIN and you need OUTER JOIN or EXISTS. Syntax will vary for RDBMS you are using.
Try this:
SELECT COUNT(*)
FROM
TableA A
WHERE
A.ColA = "Value"
AND (
EXISTS(
SELECT * FROM TableB
WHERE
ColA = "Value"
)
OR EXISTS(
SELECT * FROM TableC
WHERE
ColA = "Value"
)
)
select count(*)
from TableA
LEFT JOIN
TableB
ON TableA.ColA = TableB.ColA
LEFT JOIN
TableC
ON TableA.ColA = TableC.ColA
where TableA.ColA = "Value"
AND
(TableB.ColA IS NOT NULL OR TableC.ColA IS NOT NULL)
The idea here is:
Use LEFT JOIN so that the row is generated whether or not TableB or TableC has a row for it. If one of them or both don't have it, corresponding values will be NULL
Filter out rows for which neither TableB nor TableC have those values by requiring that at least one of them is not NULL in the WHERE clause.
Related
I have a pair of tables I need to join, I want to return any record that's in tableA, tableB or both. I think I need a FULL OUTER JOIN
This query return 1164 records
SELECT name FROM tableA
WHERE reportDay = '2022-Apr-05'
And this one return 3339 records
SELECT name FROM tableB
WHERE reportDay = '2022-Apr-05'
And this one returns 3369 records (so there must be 30 records in tableA that aren't in tableB)
select distinct name FROM tableA where reportDay = '2022-Apr-05'
union distinct
select distinct name FROM tableB where reportDay = '2022-Apr-05'
I want to obtain a list of all matching records in either table. The query above returns 3369 records, so a FULL OUTER JOIN should also return 3369 rows (I think). My best effort so far is shown below. It returns 1164 rows and returns what looks to me to be a left join between tableA and tableB.
SELECT tableA.name.*, tableB.name.*
FROM tableA
FULL OUTER JOIN tableB
ON (tableA.name = tableB.name and tableB.reportDay = '2022-Apr-05')
WHERE tableA.reportDay = '2022-Apr-05'
Help appreciated. (if this looks question looks familiar, it's a follow-on question to this one )
UPDATE - Sorry (#forpas) to keep moving the goalposts - I'm trying to match test data to real-data scenario's.
DROP TABLE tableA;
DROP TABLE tableB;
CREATE TABLE tableA (name VARCHAR(10),
reportDay DATE,
val1 INTEGER,
val2 INTEGER);
CREATE TABLE tableB (name VARCHAR(10),
reportDay DATE,
test1 INTEGER,
test2 INTEGER);
INSERT INTO tableA values ('A','2022-Apr-05',1,2),
('B','2022-Apr-05',3,4), ('C','2022-Apr-05',5,6),
('A','2022-Apr-06',1,2), ('B','2022-Apr-06',3,4),
('C','2022-Apr-06',5,6), ('Z','2022-Apr-04',5,6),
('Z','2022-Apr-06',5,6) ;
INSERT INTO tableB values ('A','2022-Apr-03',5,6),
('B','2022-Apr-04',11,22), ('B','2022-Apr-05',11,22),
('C','2022-Apr-05',33,44), ('D','2022-Apr-05',55,66),
('B','2022-Apr-06',11,22), ('C','2022-Apr-06',33,44),
('D','2022-Apr-06',55,66), ('Q','2022-Apr-06',5,6);
SELECT tableA.*, tableB.*
FROM tableA
FULL OUTER JOIN tableB
ON (tableA.name = tableB.name and tableB.reportDay = '2022-Apr-05'
AND tableA.reportDay = '2022-Apr-05' )
For this data, I'd hope to see 4 rows of data 'A' from tableA only, 'B' and 'C' from both tables, and 'D' from table B only. I'm after the 5th April records only! The query (shown above) suggested by #forpas works except that the 'A' record in tableA doesn't get returned.
UPDATE - FINAL EDIT AND ANSWER!
Ok, the solution seem to be to concetenate the two fields together before joining....
SELECT a.*, b.*
FROM tableA a FULL OUTER JOIN tableB b
ON (b.name || b.reportDay) = (a.name || a.reportDay)
WHERE (a.reportDay = '2022-Apr-05' OR a.reportDay IS NULL)
AND (b.reportDay = '2022-Apr-05' OR b.reportDay IS NULL);
The condition for the date should be placed in a WHERE clause:
SELECT a.*, b.*
FROM tableA a FULL OUTER JOIN tableB b
ON b.name = a.name AND a.reportDay = b.reportDay
WHERE '2022-Apr-05' IN (a.reportDay, b.reportDay);
or:
SELECT a.*, b.*
FROM tableA a FULL OUTER JOIN tableB b
ON b.name = a.name
WHERE (a.reportDay = '2022-Apr-05' OR a.reportDay IS NULL)
AND (b.reportDay = '2022-Apr-05' OR b.reportDay IS NULL);
See the demo.
I have two tables.
I need all records from table A except where there is a match in table B, then take table B's matching value
So if table A has a match with table B, then I need to exclude that value from the results (i.e take all records from table A and replace records from table A with the matching value from table B).
from my understanding I left joined the two tables on the matching column and then added a where clause to exclude the null values but I'm not sure if that is correct.
data:
tableA (col1 =ID, col2 =value)
1, 5
2, 3
3, 7
tableB (col1 =ID, col2 =value)
4, 6
2, 9
expected result:
5
9
7
This is the closest I've gotten but I'm not sure if it's correct:
select * from tableA tblA
left join tableB tblB
on tblA.matchingColumn = tblB.matchingColumn
where tblB.matchingColumn is null
This will return all the rows in TABLEA. If there are any matching value in TABLEB then it will be used as VALUE.
SELECT TBLA.ID
, COALESCE(TBLB.VALUE, TBLA.VALUE) VALUE
FROM TABLEA TBLA
LEFT JOIN TABLEB TBLB
ON TBLA.ID = TBLB.ID;
UPDATE - SQLFiddle for this thread
Perform a left join from tablea to tableb and use the value from a or b depending on match in tableb
select tablea.id, case when tableb.id is null then tablea.value else tableb.value end value
from tablea
left join tableb on tablea.id=tableb.id
I am stuck into a situation where I need to perform conditional join. The brief summary could be, I have 2 tables TableA and TableB.
TableA has columns A1,A2,A3,A4,A5,Condition1,Condition2
similarly TableB has columns B1,B2,Condition1,Condition2
And I need to perform join on TableA.Condition1 = TableB.Condition1 and condition join on TableA.Condition2 = TableB.Condition2, condition being TableA.Condition2 should not be null for any record first join.
In other words, if I some any record with TableA.Condition1 = TableB.Condition1 matched and at the same time TableA.Condition2 is not null for any of them then perform second join, otherwise don't perform second join.
Query could be like
SELECT A.* FROM TableA A
INNER JOIN TableB B
ON A.Condition1 = B.Condition1 -- This must be perform
AND WHEN A.Condition2 IS NULL THEN
1 = 1 -- Assuming no join here
ELSE
A.Condition2 = B.Condition2 -- perform join
END
You are only selecting from TableA, so how about using exists instead?
SELECT A.*
FROM TableA A
WHERE (A.Condition2 IS NULL AND
EXISTS (SELECT 1 FROM TableB b WHERE A.Condition1 = B.Condition1)
) AND
(A.Condition2 IS NOT NULL AND
EXISTS (SELECT 1 FROM TableB b WHERE A.Condition1 = B.Condition1 AND A.Condition2 = B.Condition2)
);
Or, if you want a JOIN:
SELECT A.*
FROM TableA A JOIN
TableB B
ON A.Condition1 = B.Condition1 AND
(A.Condition2 IS NOT NULL OR A.Condition2 = B.Condition2);
Try this may help you
SELECT A.*
FROM TableA A
INNER JOIN TableB B ON A.Condition1 = B.Condition1 AND
((A.Condition2 IS NOT NULL AND A.Condition2 = B.Condition2)
OR (A.Condition2 IS NULL) )
hard to understand your question and even harder to understand the purpose
SELECT A.*
-- join table1 and table2 on Condition1
FROM TableA A
JOIN TableB B ON A.Condition1 = B.Condition1
-- if max condition2 is null then there is nothing but nulls
JOIN ( SELECT MAX(Condition2) Condition2 FROM TableA A2 ) A2
-- in that case every row resulting from join1 goes
ON A2.Condition2 IS NULL
-- otherwise use condition2 but replace nulls with some placeholder
-- or maybe you have either all null or no nulls
OR COALESCE (A.Condition2,'null') = COALESCE (B.Condition2,'null')
;
I have Query in Access that I'm building in SQL Server.
Access:
DELETE DISTINCT * from [TableA] INNER JOIN TableB
ON [TableA].[Column1]=[TableB].[column1]
AND [TableA].[Column2]=[TableB].[column2]
I know I could use
Delete from tableA where ID in (
Select * from from [TableA] INNER JOIN TableB
ON [TableA].[Column1]=[TableB].[column1]
AND [TableA].[Column2]=[TableB].[column2])
But I get an error saying "Only one expression can be specified in the select list when the subquery is not introduced with EXISTS"
My Goal is to delete the Distinct records from the Access query mentioned at the top.
You want to delete the rows in TableA that are in TableB, according to the column matches. How about doing this:
delete from tableA
where exists (select 1
from tableB
where tableA.Column1 = tableB.Column1 and tableA.column2 = tableB.column2
);
This seems to be the intent of what you are trying to do.
In the sub-query u have to select the ID column from the respective table that is the only column u need
DELETE a
FROM tableA a
JOIN (SELECT DISTINCT Column1 ,column2
FROM tableA
WHERE EXISTS (SELECT 1
FROM tableB
WHERE tableA.Column1 = tableB.Column1
AND tableA.column2 = tableB.column2)) b
ON A.Column1 = B.Column1
AND A.column2 = B.column2
Here are my tables:
create table tableA (id int, type varchar(5))
insert into tableA (ID,TYPE)
values
(101,'A'),
(101,'C'),
(101,'D'),
(102,'A'),
(102,'B'),
(103,'A'),
(103,'C')
create table tableB (id int, type varchar(5), isActive bit)
insert into tableB (id, type, isActive)
Values
(101,'A',1),
(101,'B',0),
(101,'C',0),
(101,'D',1),
(102,'A',1),
(102,'B',0),
(102,'C',1),
(102,'D',1),
(103,'A',1),
(103,'B',1),
(103,'C',1),
(103,'D',1)
Now, I want to do two things here:
1) Find the rows that are present in tableA but isActive = 0 in tableB. (done)
select A.* from tableA A
join tableB B
on A.id = B.id and A.type = B.type
where B.isactive = 0
2) Find the rows that are missing in tableA but isActive = 1 in tableB.
For example ID 103, type B is active in tableB but is missing in tableA.
I don't care about existance of type D in tableA because I am only checking the last entry in tableA which is C.
Also, ABCD is in order for all IDs, they can be active or inactive.
Thanks for your help!
My effort: (not working)
select A.* from tableA A
where exists (
select B.* from tableA A
join tableB B
on a.id = b.id
where b.isActive = 1
order by b.id,b.type
)
SQLFiddle
I think you are looking for something like the following:
select B.* from tableB B
left join tableA A
on B.id = A.id and B.type = A.type
where B.isActive = 1
and A.id is null
order by B.id, B.type
By using the left join, it means that rows in tableB that have no rows to join with in tableA will have all A.* columns null. This then allows you to add the where clause to check where the tableA records are null thus determining what is contained within tableB that is active and not in tableA