I am using DB 2 and i am trying to write a query which checks multiple columns against a given set of values.Like field a, field b and field c against values x,y,z,f. One way that i can think for is writing same condition 3 times with or i.e. field a in ('x','y','z','f') or field b in .... and so on . Please let me know if there is some other efficient and easy way to accomplish this. I am looking for a query like if any of the condition is true return yes else no . Please suggest !
This may or may not work on as400:
create table a (a int not null, b int not null);
insert into a (a,b) values (1,1),(1,3),(2,3),(0,23);
select a.*
from a
where a in (1,2) or b in (1,2);
A B
----------- -----------
1 1
1 3
2 3
Rewriting as a join:
select a.*
from a
join ( values (1),(2) ) b (x)
on b.x in (a.a, a.b);
A B
----------- -----------
1 1
1 3
2 3
Assuming the column data types are the same, Create a subquery joining all the columns you want to search with your IN into one column with a union
SELECT *
FROM (
SELECT
YOUR_TABLE_PRIMARY_KEY
,A AS Col
FROM YOUR_TABLE
UNION ALL
SELECT
YOUR_TABLE_PRIMARY_KEY
,B AS Col
FROM YOUR_TABLE
UNION ALL
SELECT
YOUR_TABLE_PRIMARY_KEY
,C AS Col
FROM YOUR_TABLE
) AS SQ
WHERE
SQ.Col IN ('x','y','z','f')
Make sure to include the table key so you know which row the data refers to
You can create a regular expression that describe the set of characters and use it with xquery
Assuming you're on a supported version of the OS (tested on 7.1 TR6), this should work...
with sel (val) as (values ('x'),('y'),('f'))
select * from mytbl
where flda in (select val from sel)
or fldb in (select val from sel)
or fldc in (select val from sel)
Expanding on the above since your OP asked for "condition is true return yes else no"
Assuming you've got the key to a row to check, would 'yes' or the empty set be good enough? somekey is the key for the row you want to check.
with sel (val) as (values ('x'),('y'),('f'))
select 'yes' from mytbl
where thekey = somekey
and ( flda in (select val from sel)
or fldb in (select val from sel)
or fldc in (select val from sel)
)
It's actually rather difficult to return a value when you don't have a matching row. Here's one way. Note I've switch to 1=yes, 0=no..
with sel (val) as (values ('x'),('y'),('f'))
select 1 from mytbl
where thekey = somekey
and ( flda in (select val from sel)
or fldb in (select val from sel)
or fldc in (select val from sel)
)
UNION ALL
select 0
from sysibm.sysdummy1
order by 1 desc
fetch first row only
Related
I have a select query that returns multiple rows, and I want to check if all rows are the same. So something like this:
anything_other_than(123) in (select id from foo)
So, if select id from foo returns 111,222,123,333 the statement above is false, and if select id from foo returns 123,123,123 it's true. How can I achieve this?
A simple solution is to use the = ALL operator:
SELECT 123 = ALL (SELECT id FROM foo);
This solution also stop scanning the result as soon as the first non-matching value is found.
Another option is to use EXISTS with a where condition:
select not exists (select *
from the_table
where id <> 123);
Run this:
select count(distinct id) = 1 and count(*) > 1 from foo;
count(distinct id) will return 1 if all the rows are the same
and count(*) will return the total number of rows.
If this returns true then you have more than 1 rows and all the rows are the same.
You can use something like this -
select x, IF(x > 1, "FALSE", "TRUE") from
(SELECT count(distinct(A.id)) as x FROM foo as A) as B;
Do refer this https://www.w3schools.com/sql/func_mysql_if.asp
Have a scenario to select the value from table where range condition is present in source table.
Like,
TableA
ID value condition
1 20 A-M
2 50 N-Z
Select value from TableA where condition = 'C%'
--want to select TableA value from TableB by passing person name starts with like,
-- Here C is item name starts with
-- Should compare with range (A-M) and return first row.
-- Condition column is varchar(3)
I have seen the solution on other way where range can be compared with input value, but here the range is present in the source table. Please help.
If I have understood what you are after correctly you can use
SELECT TOP 1 B.*
FROM TableB B
WHERE B.Name LIKE (SELECT CONCAT('[',condition,']%') FROM TableA WHERE ID =1)
ORDER BY B.Id
If I understand correctly, you should be structuring TableA as:
ID value Lower Upper
1 20 A M
2 50 N Z
Then you want:
select a.*
from tableA a
where left(#name, 1) between a.lower and a.upper;
You can get this to work with your format, by doing:
select a.*
from tableA a
where left(#name, 1) between left(a.condition) and right(a.condition);
But I don't recommend that. Better to store the condition in two columns.
I would use QUOTENAME() function as
SELECT *
FROM TableA
WHERE #Condition LIKE QUOTENAME(Condition);
This will be as
WHERE 'C' LIKE [A-M] --return True
Demo1
Demo2
Always you should try to add data and DDL for setup correctly the test scenario, here my proposed solution:
DECLARE #SourceA AS TABLE
(
ID INT,
Value INT,
Condition VARCHAR(100)
);
INSERT INTO #SourceA ( ID ,
Value ,
Condition
)
VALUES ( 1 , -- ID - int
110 , -- Value - int
'A-M' -- Condition - varchar(100)
),(2,250,'N-Z')
DECLARE #Alphabet VARCHAR(200)='A,B,C,D,E,F,G,H,I,J,K,L,M,N,O,P,Q,R,S,T,U,V,W,X,Y,Z';
; WITH MyCTE AS
(
SELECT ID,Value,Condition, SUBSTRING(#Alphabet, PATINDEX('%'+ LEFT(Condition,1) + '%' ,#Alphabet),(LEN(#Alphabet)-PATINDEX('%'+ RIGHT(Condition,1) + '%' ,#Alphabet))+1) AS FormattedCondition
FROM #SourceA
)
SELECT * FROM MyCTE
WHERE MyCTE.FormattedCondition LIKE '%C%'
I am searching with a query
--Code Format
SELECT COLA,COLB,COLC from MYTABLE where SWITCH IN (1,2,3);
If MYTABLE does not contain rows with SWITCH 1,2 or 3 I need default values returned along with the SWITCH value. How do I do it?
Below is my table format
COLA | COLB | COLC | SWITCH
------------------------------
A B C 1
a b c 2
i want a query when I search with
select * from MYTABLE where switch in (1,2,3)
That gets results like this --
COLA | COLB | COLC | SWITCH
------------------------------
A B C 1
a b c 2
NA NA NA 3
--Check to see if any row exists matching your conditions
IF NOT EXISTS (SELECT COLA,COLB,COLC from MYTABLE where SWITCH IN (1,2,3))
BEGIN
--Select your default values
END
ELSE
BEGIN
--Found rows, return them
SELECT COLA,COLB,COLC from MYTABLE where SWITCH IN (1,2,3)
END
if not exists( SELECT 1 from MYTABLE where SWITCH IN (1,2,3))
select default_value
How about:
SELECT COLA,COLB,COLC from MYTABLE where SWITCH IN (1,2,3)
union select 5555, 6666, 7777 where not exists (
SELECT COLA,COLB,COLC from MYTABLE where SWITCH IN (1,2,3)
);
5555, 6666, 7777 being the default row in case there aren't any rows matching your criteria.
Here is one way to tackle this. You need a table of the SWITCH values you want to look at. Then a simple left join makes this super easy.
select ColA
, ColB
, ColC
v.Switch
from
(
values
(1)
, (2)
, (3)
)v (Switch)
left join YourTable yt on yt.Switch = v.Switch
You can Use a Split Function And Left Join As Shown Below:
Select ISNULL(ColA,'NA') As ColA,ISNULL(ColB,'NA') As ColB,ISNULL(ColC,'NA') As ColC,ISNULL(Switch,a.splitdata)
from [dbo].[fnSplitString]('1,2,3',',') a
LEFT JOIN #MYTABLE t on a.splitdata=t.Switch
[dbo].[fnSplitString] is a Split Function with 2 arguments - Delimeter Separated String and Delimeter and Output a Table.
EDIT:
Given the new explanation, I changed the answer completely. I think I got your question now:
SELECT * FROM MYTABLE AS mt
RIGHT JOIN (SELECT 1 AS s UNION SELECT 2 AS s UNION SELECT 3 AS s) AS st
ON st.s = mt.SWITCH
You could change the SELECT 1 AS s UNION SELECT 2 AS s UNION SELECT 3 AS spart to a subquery that results in all possible values SWITCH could assume. E.g.:
SELECT DISTINCT SWITCH FROM another_table_with_all_switches
If all want is the value of switch that is not in MYTABLE, not the whole table with null values, you could try:
SELECT * FROM
(SELECT 1 AS s UNION SELECT 2 AS s UNION SELECT 3) AS st
WHERE st.s NOT IN (SELECT DISTINCT SWITCH FROM MYTABLE)
I would like to use the IN clause, but with the convert function.
Basically, I have a table (A) with the column of type int.
But in the other table (B) I Have values which are of type varchar.
Essentially, what I am looking for something like this
select *
from B
where myB_Column IN (select myA_Columng from A)
However, I am not sure if the int from table A, would map / convert / evaluate properly for the varchar in B.
I am using SQL Server 2008.
You can use CASE statement in where clause like this and CAST only if its Integer.
else 0 or NULL depending on your requirements.
SELECT *
FROM B
WHERE CASE ISNUMERIC(myB_Column) WHEN 1 THEN CAST(myB_Column AS INT) ELSE 0 END
IN (SELECT myA_Columng FROM A)
ISNUMERIC will be 1 (true) for Decimal values as-well so ideally you should implement your own IsInteger UDF .To do that look at this question
T-sql - determine if value is integer
Option #1
Select * from B where myB_Column IN
(
Select Cast(myA_Columng As Int) from A Where ISNUMERIC(myA_Columng) = 1
)
Option #2
Select B.* from B
Inner Join
(
Select Cast(myA_Columng As Int) As myA_Columng from A
Where ISNUMERIC(myA_Columng) = 1
) T
On T.myA_Columng = B.myB_Column
Option #3
Select B.* from B
Left Join
(
Select Cast(myA_Columng As Int) As myA_Columng from A
Where ISNUMERIC(myA_Columng) = 1
) T
On T.myA_Columng = B.myB_Column
I will opt third one. Reason is below mentioned.
Disadvantages of IN Predicate
Suppose I have two list objects.
List 1 List 2
1 12
2 7
3 8
4 98
5 9
6 10
7 6
Using Contains, it will search for each List-1 item in List-2 that means iteration will happen 49 times !!!
You can also use exists caluse,
select *
from B
where EXISTS (select 1 from A WHERE CAST(myA_Column AS VARCHAR) = myB_Column)
You can use below query :
select B.*
from B
inner join (Select distinct MyA_Columng from A) AS X ON B.MyB_Column = CAST(x.MyA_Columng as NVARCHAR(50))
Try it by using CAST()
SELECT *
FROM B
WHERE CAST(myB_Column AS INT(11)) IN (
SELECT myA_Columng
FROM A
)
I am working on a query that is fairly similar the following:
CREATE TABLE #test (a char(1), b char(1))
INSERT INTO #test(a,b) VALUES
('A',NULL),
('A','B'),
('B',NULL),
('B',NULL)
SELECT DISTINCT a,b FROM #test
DROP TABLE #test
The result is, unsurprisingly,
a b
-------
A NULL
A B
B NULL
The output I would like to see in actuality is:
a b
-------
A B
B NULL
That is, if a column has a value in some records but not in others, I want to throw out the row with NULL for that column. However, if a column has a NULL value for all records, I want to preserve that NULL.
What's the simplest/most elegant way to do this in a single query?
I have a feeling that this would be simple if I weren't exhausted on a Friday afternoon.
Try this:
select distinct * from test
where b is not null or a in (
select a from test
group by a
having max(b) is null)
You can get the fiddle here.
Note if you can only have one non-null value in b, this can be simplified to:
select a, max(b) from test
group by a
Try this:
create table test(
x char(1),
y char(1)
);
insert into test(x,y) values
('a',null),
('a','b'),
('b', null),
('b', null)
Query:
with has_all_y_null as
(
select x
from test
group by x
having sum(case when y is null then 1 end) = count(x)
)
select distinct x,y from test
where
(
-- if a column has a value in some records but not in others,
x not in (select x from has_all_y_null)
-- I want to throw out the row with NULL
and y is not null
)
or
-- However, if a column has a NULL value for all records,
-- I want to preserve that NULL
(x in (select x from has_all_y_null))
order by x,y
Output:
X Y
A B
B NULL
Live test: http://sqlfiddle.com/#!3/259d6/16
EDIT
Seeing Mosty's answer, I simplified my code:
with has_all_y_null as
(
select x
from test
group by x
-- having sum(case when y is null then 1 end) = count(x)
-- should have thought of this instead of the code above. Mosty's logic is good:
having max(y) is null
)
select distinct x,y from test
where
y is not null
or
(x in (select x from has_all_y_null))
order by x,y
I just prefer CTE approach, it has a more self-documenting logic :-)
You can also put documentation on non-CTE approach, if you are conscious of doing so:
select distinct * from test
where b is not null or a in
( -- has all b null
select a from test
group by a
having max(b) is null)
;WITH CTE
AS
(
SELECT DISTINCT * FROM #test
)
SELECT a,b
FROM CTE
ORDER BY CASE WHEN b IS NULL THEN 9999 ELSE b END ;
SELECT DISTINCT t.a, t.b
FROM #test t
WHERE b IS NOT NULL
OR NOT EXISTS (SELECT 1 FROM #test u WHERE t.a = u.a AND u.b IS NOT NULL)
ORDER BY t.a, t.b
This is a really weird requirement. I wonder how you need it.
SELECT DISTINCT a, b
FROM test t
WHERE NOT ( b IS NULL
AND EXISTS
( SELECT *
FROM test ta
WHERE ta.a = t.a
AND ta.b IS NOT NULL
)
)
AND NOT ( a IS NULL
AND EXISTS
( SELECT *
FROM test tb
WHERE tb.b = t.b
AND tb.a IS NOT NULL
)
)
Well, I don't particularly like this solution, but it seems the most appropriate to me. Note that your description of what you want sounds exactly like what you get with a LEFT JOIN, so:
SELECT DISTINCT a.a, b.b
FROM #test a
LEFT JOIN #test b ON a.a = b.a
AND b.b IS NOT NULL
SELECT a,b FROM #test t where b is not null
union
SELECT a,b FROM #test t where b is null
and not exists(select 1 from #test where a=t.a and b is not null)
Result:
a b
---- ----
A B
B NULL
I'll just put here a mix of two answers that solved my issue, because my View was more complex
--IdCompe int,
--Nome varchar(30),
--IdVanBanco int,
--IdVan int
--FlagAtivo bit,
--FlagPrincipal bit
select IdCompe
, Nome
, max(IdVanBanco)
, max(IdVan)
, CAST(MAX(CAST(FlagAtivo as INT)) AS BIT) FlagAtivo
, CAST(MAX(CAST(FlagPrincipal as INT)) AS BIT) FlagPrincipal
from VwVanBanco
where IdVan = {IdVan} or IdVan is null
group by IdCompe, Nome order by IdCompe asc
Thanks to mosty mostacho and
kenwarner