Say I have an oracle table that looks like this:
So, a sample can have 2 rows, one where test_value == value1 and one where test_value == value2, or one of them can be missing.
If I want to query for all the samples that have a value1 row but NOT a value2 row (i.e., all samples with a missing value2 row), how would I do that?
(I.e., in my example, I would expect to find sample2.)
Use not exists:
select *
from t
where t.test_value = 'value1' and
not exists(select 1 form t t2 where t2.sample = t.sample and t2.test_value = 'value2');
If you just want the samples and not the complete rows, then aggregation can also be used:
select sample
from t
where test_value in ('value_1', 'value_2')
group by sample
having min(test_value) = max(test_value) and
max(test_value) = 'value1';
Actually, for your particular strings, that can be simplified to:
having max(test_value) = 'value1'
try this, it detects the cases of samples which has only 1 value, and then checks that this value is value1.
SELECT SAMPLE
FROM
(
SELECT SAMPLE, SUM(CASE WHEN TEST_VALUE = 'value1' THEN 1 ELSE 0 END) AS IS_TEST_VALUE1
FROM tbl
GROUP BY SAMPLE
HAVING COUNT(*) = 1
) AS X
WHERE IS_TEST_VALUE1 = 1
Related
Ok here goes:
MyTableName
KEY Value1
1 ABC
1 DEF
1 GHI
2 ABC
2 DEF
2 YUI
I have a child table that is linked via a Key (stated above)
I need to find records, linked to the parent table (i have no issues with my join) where value 1 meets conditions and does not meet certain conditions.
So, for my Example, I want to retrieve the value '1' from the "KEY" above, because my need is where value 1 = 'ABC' or value 1 = 'DEF' but value 1 != YUI,
so I would want '1' to come back, but not 2
SELECT KEY, count(*)
FROM MyTableName
WHERE (value1 = 'ABC'
OR value1 = 'DEF')
AND value1 != 'YUI'
GROUP BY KEY
HAVING count(KEY) = 2
The above statement, find both Key 1 and 2, where I need it only to find Key 1.
Can anyone help?
Use the HAVING clause with conditional counts:
select key
from mytablename
group by key
having count(case when value1 in ('ABC','DEF') then 1 end) > 0
and count(case when value1 = 'YUI' then 1 end) = 0;
(You can add where value1 in ('ABC','DEF','YUI'), which may speed up the query, because you are not interested in rows containing other values.)
(Some people prefer to include an explicit else branch: count(case when value1 = 'YUI' then 1 else null end) and others prefer sum(case when value1 = 'YUI' then 1 else 0 end). That's a matter of personal preference.)
I have a historization table called CUR_VALID. This table looks something like this:
ID CUR_VALID
1 N
1 N
1 Y
2 N
2 Y
3 Y
For every ID there needs to be one Y. If there is no Y or multiple Y there is something wrong. The statment for checking if there are multiple Y I already got. Now I only need to check for every ID if there is one Y existing. Im just not sure how to do that. This is what I have so far. So how do I check if the Value 'Y' exists?
SELECT Count(1) [Number of N]
,MAX(CUR_VALID = 'N')
,[BILL_ID]
,[BILL_MONTH]
,[BILL_SRC_ID]
FROM db.dbo.table
GROUP BY [BILL_ID]
,[BILL_MONTH]
,[BILL_SRC_ID]
Having MAX(CUR_VALID = 'N') > 1
Why are you fiddling with 'N' when you are interested in 'Y'?
Use conditional aggregation to get the count of the value your are interested in.
SELECT
COUNT(*) AS number_of_all,
COUNT(CASE WHEN cur_valid = 'Y' THEN 1 END) AS number_of_y,
COUNT(CASE WHEN cur_valid = 'N' THEN 1 END) AS number_of_n,
bill_id,
bill_month,
bill_src_id,
FROM db.dbo.table
GROUP BY bill_id, bill_month, bill_src_id;
Add a HAVING clause in order to get only valid
HAVING COUNT(CASE WHEN cur_valid = 'Y' THEN 1 END) = 1
or invalid
HAVING COUNT(CASE WHEN cur_valid = 'Y' THEN 1 END) <> 1
bills.
The following query will give you the list of id for which your integrity condition is not met: For every ID there needs to be one Y. If there is no Y or multiple Y there is something wrong.
select T1.id from table T1 where (select count(*) from table T2 where T2.id=T1.id and T2.CUR_VALID='Y')!=1
This query returns both not having at least one 'Y' value and more than one 'Y' value ID's.
First, sum up the Y values and relate to each id, then select not 1 ones from that table.
select * from (
select ID, SUM(case when CUR_VALID = 'Y' then 1 else 0 end) as CNT
from table
group by ID
) b where b.CNT <> 1
DBFiddle
As I understand, you want to get all the id for which your integrity check passes. And integrity check for you means, there is only one row with CUR_VALID value equal to Y in the CUR_VALID table.
This can be achieved by a group by clause:
select id from CUR_VALID
where CUR_VALID.CUR_VALID = 'Y'
group by id
having count(CUR_VALID.CUR_VALID) = 1;
I am writing data to a table and allocating a "group-id" for each batch of data that is written. To illustrate, consider the following table.
GroupId Value
------- -----
1 a
1 b
1 c
2 a
2 b
3 a
3 b
3 c
3 d
In this example, there are three groups of data, each with similar but varying values.
How do I query this table to find a group that contains a given set of values? For instance, if I query for (a,b,c) the result should be group 1. Similarly, a query for (b,a) should result in group 2, and a query for (a, b, c, e) should result in the empty set.
I can write a stored procedure that performs the following steps:
select distinct GroupId from Groups -- and store locally
for each distinct GroupId: perform a set-difference (except) between the input and table values (for the group), and vice versa
return the GroupId if both set-difference operations produced empty sets
This seems a bit excessive, and I hoping to leverage some other commands in SQL to simplify. Is there a simpler way to perform a set-comparison in this context, or to select the group ID that contains the exact input values for the query?
This is a set-within-sets query. I like to solve it using group by and having:
select groupid
from GroupValues gv
group by groupid
having sum(case when value = 'a' then 1 else 0 end) > 0 and
sum(case when value = 'b' then 1 else 0 end) > 0 and
sum(case when value = 'c' then 1 else 0 end) > 0 and
sum(case when value not in ('a', 'b', 'c') then 1 else - end) = 0;
The first three conditions in the having clause check that each elements exists. The last condition checks that there are no other values. This method is quite flexible, for various exclusions and inclusion conditions on the values you are looking for.
EDIT:
If you want to pass in a list, you can use:
with thelist as (
select 'a' as value union all
select 'b' union all
select 'c'
)
select groupid
from GroupValues gv left outer join
thelist
on gv.value = thelist.value
group by groupid
having count(distinct gv.value) = (select count(*) from thelist) and
count(distinct (case when gv.value = thelist.value then gv.value end)) = count(distinct gv.value);
Here the having clause counts the number of matching values and makes sure that this is the same size as the list.
EDIT:
query compile failed because missing the table alias. updated with right table alias.
This is kind of ugly, but it works. On larger datasets I'm not sure what performance would look like, but the nested instances of #GroupValues key off GroupID in the main table so I think as long as you have a good index on GroupID it probably wouldn't be too horrible.
If Object_ID('tempdb..#GroupValues') Is Not Null Drop Table #GroupValues
Create Table #GroupValues (GroupID Int, Val Varchar(10));
Insert #GroupValues (GroupID, Val)
Values (1,'a'),(1,'b'),(1,'c'),(2,'a'),(2,'b'),(3,'a'),(3,'b'),(3,'c'),(3,'d');
If Object_ID('tempdb..#FindValues') Is Not Null Drop Table #FindValues
Create Table #FindValues (Val Varchar(10));
Insert #FindValues (Val)
Values ('a'),('b'),('c');
Select Distinct gv.GroupID
From (Select Distinct GroupID
From #GroupValues) gv
Where Not Exists (Select 1
From #FindValues fv2
Where Not Exists (Select 1
From #GroupValues gv2
Where gv.GroupID = gv2.GroupID
And fv2.Val = gv2.Val))
And Not Exists (Select 1
From #GroupValues gv3
Where gv3.GroupID = gv.GroupID
And Not Exists (Select 1
From #FindValues fv3
Where gv3.Val = fv3.Val))
so basicially there is 1 question and 1 problem:
1. question - when I have like 100 columns in a table(and no key or uindex is set) and I want to join or subselect that table with itself, do I really have to write out every column name?
2. problem - the example below shows the 1. question and my actual SQL-statement problem
Example:
A.FIELD1,
(SELECT CASE WHEN B.FIELD2 = 1 THEN B.FIELD3 ELSE null FROM TABLE B WHERE A.* = B.*) AS CASEFIELD1
(SELECT CASE WHEN B.FIELD2 = 2 THEN B.FIELD4 ELSE null FROM TABLE B WHERE A.* = B.*) AS CASEFIELD2
FROM TABLE A
GROUP BY A.FIELD1
The story is: if I don't put the CASE into its own select statement then I have to put the actual rowname into the GROUP BY and the GROUP BY doesn't group the NULL-value from the CASE but the actual value from the row. And because of that I would have to either join or subselect with all columns, since there is no key and no uindex, or somehow find another solution.
DBServer is DB2.
So now to describing it just with words and no SQL:
I have "order items" which can be divided into "ZD" and "EK" (1 = ZD, 2 = EK) and can be grouped by "distributor". Even though "order items" can have one of two different "departements"(ZD, EK), the fields/rows for "ZD" and "EK" are always both filled. I need the grouping to consider the "departement" and only if the designated "departement" (ZD or EK) is changing, then I want a new group to be created.
SELECT
(CASE WHEN TABLE.DEPARTEMENT = 1 THEN TABLE.ZD ELSE null END) AS ZD,
(CASE WHEN TABLE.DEPARTEMENT = 2 THEN TABLE.EK ELSE null END) AS EK,
TABLE.DISTRIBUTOR,
sum(TABLE.SOMETHING) AS SOMETHING,
FROM TABLE
GROUP BY
ZD
EK
TABLE.DISTRIBUTOR
TABLE.DEPARTEMENT
This here worked in the SELECT and ZD, EK in the GROUP BY. Only problem was, even if EK was not the designated DEPARTEMENT, it still opened a new group if it changed, because he was using the real EK value and not the NULL from the CASE, as I was already explaining up top.
And here ladies and gentleman is the solution to the problem:
SELECT
(CASE WHEN TABLE.DEPARTEMENT = 1 THEN TABLE.ZD ELSE null END) AS ZD,
(CASE WHEN TABLE.DEPARTEMENT = 2 THEN TABLE.EK ELSE null END) AS EK,
TABLE.DISTRIBUTOR,
sum(TABLE.SOMETHING) AS SOMETHING,
FROM TABLE
GROUP BY
(CASE WHEN TABLE.DEPARTEMENT = 1 THEN TABLE.ZD ELSE null END),
(CASE WHEN TABLE.DEPARTEMENT = 2 THEN TABLE.EK ELSE null END),
TABLE.DISTRIBUTOR,
TABLE.DEPARTEMENT
#t-clausen.dk: Thank you!
#others: ...
Actually there is a wildcard equality test.
I am not sure why you would group by field1, that would seem impossible in your example. I tried to fit it into your question:
SELECT FIELD1,
CASE WHEN FIELD2 = 1 THEN FIELD3 END AS CASEFIELD1,
CASE WHEN FIELD2 = 2 THEN FIELD4 END AS CASEFIELD2
FROM
(
SELECT * FROM A
INTERSECT
SELECT * FROM B
) C
UNION -- results in a distinct
SELECT
A.FIELD1,
null,
null
FROM
(
SELECT * FROM A
EXCEPT
SELECT * FROM B
) C
This will fail for datatypes that are not comparable
No, there's no wildcard equality test. You'd have to list every field you want tested individually. If you don't want to test each individual field, you could use a hack such as concatenating all the fields, e.g.
WHERE (a.foo + a.bar + a.baz) = (b.foo + b.bar + b.az)
but either way, you're listing all of the fields.
I might tend to solve it something like this
WITH q as
(SELECT
Department
, (CASE WHEN DEPARTEMENT = 1 THEN ZD
WHEN DEPARTEMENT = 2 THEN EK
ELSE null
END) AS GRP
, DISTRIBUTOR
, SOMETHING
FROM mytable
)
SELECT
Department
, Grp
, Distributor
, sum(SOMETHING) AS SumTHING
FROM q
GROUP BY
DEPARTEMENT
, GRP
, DISTRIBUTOR
If you need to find all rows in TableA that match in TableB, how about INTERSECT or INTERSECT DISTINCT?
select * from A
INTERSECT DISTINCT
select * from B
However, if you only want rows from A where the entire row matches the values in a row from B, then why does your sample code take some values from A and others from B? If the row matches on all columns, then that would seem pointless. (Perhaps your question could be explained a bit more fully?)
I currently have 2 columns for my database and I'm trying to return all values in column 1 that don't contain a certain value in column two:
ex: Column 1 has 9 digit random value, sometimes repeated. There are 4 different options for column 2; P1, P2, P3, P4.
I'm trying to only display values in column 1 that don't have a value of P4 in column 2. If they don't have a P4, then I want them all to be displayed, but once a Column 1 value is associated with P4, I don't want any of the column 1 values displayed. This process will continue through all column 1 values until the only values displayed in column 1 are values that do not have a P4 column 2 value associated with them.
You mean something like this?
SELECT *
FROM YOUR_TABLE
WHERE COLUMN1 NOT IN (
SELECT COLUMN1
FROM YOUR_TABLE
WHERE COLUMN2 = 'P4'
)
Wouldn't this just be
SELECT column1 FROM <table> WHERE column2 != 'P4'
This is an example of a query where you are looking at sets within sets -- that is, sets of column2 within values of column1. I prefer using group by and having for these queries:
select column1
from t
group by column1
having sum(case when column2 = 'P4' then 1 else 0 end) = 0
To get all the values, you would join back to the original table:
select t.*
from t join
(select column1
from t
group by column1
having sum(case when column2 = 'P4' then 1 else 0 end) = 0
) c1
on t.column1 = c1.column1