Sample Table : MyTable1
Col1 | Col2 | Col3
3 10 5
10 9 40
1 2 6
The Output must be:
NewColumn
10
40
6
As you can see, I just need to get the highest value from each row..
Is it possible by just using a sql select query?
Thanks in advance
You will need to use the MS Access function IIF()
IIF(condition, valueiftrue, valueiffalse)
condition is the value that you want to test.
valueiftrue is the value that is returned if condition evaluates to
TRUE.
valueiffalse is the value that is returned if condition evaluates to
FALSE.
so your query would be
SELECT IIf(C12 > Col3, C12, Col3) as newColumn
FROM
(
select IIF(Col1 > Col2, Col1, Col2) as C12, Col3
from mytable1
) x
I wonder if this would work in MS Access (can't verify myself, I'm afraid):
SELECT
(
SELECT MAX(Col)
FROM (
SELECT Col1 AS Col UNION ALL
SELECT Col2 UNION ALL
SELECT Col3
) s
) AS NewColumn
FROM yourtable
This works in the other family of database products by the same vendor, so I thought they might just happen to have added support for this in MS Access too.
Example which works:
Table1:
Col - Text
Col1 - Number
Col2 - Number
Col3 - Number
Col4 - Number
Data:
col; col1; col2; col3; col4;
a; 1; 4; 6; 7;
b; 3; 66; 23; 235;
c; 34; 634; 11; 23;
Query:
SELECT Col, Max(colx) AS MaxOfColx
FROM
(
SELECT Col, Col1 AS Colx From Table1 UNION ALL
SELECT Col, Col2 AS Colx From Table1 UNION ALL
SELECT Col, Col3 AS Colx From Table1 UNION ALL
SELECT Col, Col4 AS Colx From Table1
)
group by Col
Result:
Col; MaxOfColx
a; 7
b; 235
c; 634
This will work for as many columns as you need.
Related
I want to do something like this using BigQuery.
Input Table
Col1
Col2
Col3
Col4
1
A,B,C
123
789
Output Table
ID
COL
VALUE
1
COL1
1
1
COL2
A,B,C
1
COL3
123
1
COL4
789
I got this in hive with LATERAL VIEW explode(MAP), but I can't get the same in bigquery.
Consider below approach
select id, col, value
from (select *, row_number() over() as id from your_table)
unpivot (value for col in (Col1, Col2, Col3, Col4))
f apply to sample data in your question
with your_table as (
select '1' Col1, 'A,B,C' Col2, '123' Col3, '789' Col4
)
output is
Note - this particular approach requires all columns (Col1 - Col4) to be of the same type. If this is not a case you will need first apply cast for some of those to make them string
If it's a discrete number of columns, you can use UNIONs for this...
select id, 'Col1' as Column, col1 as Value
from table
union all
select id, 'Col2' as Column, col2 as Value
from table
union all
select id, 'Col3' as Column, col3 as Value
from table
Is it possible to write MS SQL query for this case? If there is pair with 1 and -1 , I don't want select those entries at all.
COL1
COL2
NOTE
A
1
I don't want select this entry becase is in pair with A -1
A
-1
I don't want select this entry becase is in pair with A 1
A
1
OK to select - no pair (no -1 for this A )
B
1
OK to select - no pair
C
1
OK to select - no pair
D
1
I don't want select this entry because is in pair with D -1
D
-1
I don't want select this entry because is in pair with D 1
I understand there is 1s and -1s and these are the only possible values for col2. If this is the case and there is at most one row difference, then you can just add the values up:
select col1, sum(col2)
from mytable
group by col1
having sum(col2) <> 0;
If there can be more rows different or there exist other values beside 1 and -1, then we must generate row numbers.
select col1, max(col2)
from
(
select
col1,
col2,
row_number() over (partition by col1, col2 order by col2) as rn
from mytable
) numbered
group by col1, rn
having count(*) = 1;
One method is aggregation. Assuming there are only -1 and 1 and no duplicates with the same sign:
select col1, max(col2), col3
from t
group by col1, col3
having count(*) = 1;
Alternatively, you could use `not exists:
select t.*
from t
where not exists (select 1
from t t2
where t2.col3 = c.col3 and t2.col1 = t.col1 and
t2.col2 = - t.col1
);
If for any value of Col1 sum of 1 and -1 is not 0, it means that it has unpaired value.
try this:
select *
from t
where col1 in
(select col1 from t group by col1 having sum(col2) <> 0);
--Table_1
col1 col2
............
123 abc
456 def
123 def
select * from Table_1 where col1 in (123,456) and col2 in (abc,def);
I want the output to match the row containing just '123' from "col1" and 'abc' from "col2" , and not '123' from col1 and 'def' from 'col2'.
The list in IN clause should match accordingly in a linear manner.
select * from Table_1 where col1 in (123,456) and col2 in (abc,def);
O/P
col1 col2
123 abc
456 def
You may use tuples for comparison of a combination of multiple columns.
select *
from Table_1
where (col1,col2) in ( (123,'abc'),(456,'def'), (789,'abc') );
Demo
You can try to use row_number window function to make it.
SELECT col1,col2
from (
select col1,col2,row_number() over(partition by col1 order by col2) rn
from Table_1
where col1 in (123,456) and col2 in ('abc','def')
) t1
where rn = 1
sqlfiddle
I need to get to first (min) date from a set of 4 (or more) columns.
I tried
select min (col1, col2, col3) from tbl
which is obviouslly wrong.
let's say I have these 4 columns
col1 | col2 | col3 | col4
1/1/17 | 2/2/17 | | 3/3/17
... in this case what I want to get is the value in col1 (1/1/17). and Yes, these columns can include NULLs.
I am running this in dashDB
the columns are Date data type,
there is no ID nor Primary key column in this table,
and I need to do this for ALL rows in my query,
the columns are NOT in order. meaning that col1 does NOT have to be before col2 or it has to be null AND col2 does NOT have to be before col3 or it has to be NULL .. and so on
If your DB support least function, it is the best approach
select
least
(
nvl(col1,TO_DATE('2901-01-01','YYYY-MM-DD')),
nvl(col2,TO_DATE('2901-01-01','YYYY-MM-DD')),
nvl(col3,TO_DATE('2901-01-01','YYYY-MM-DD')),
nvl(col4,TO_DATE('2901-01-01','YYYY-MM-DD'))
)
from tbl
Edit: If all col(s) are null, then you can hardcode the output as null. The below query should work. I couldn't test it but this should work.
select
case when
least
(
nvl(col1,TO_DATE('2901-01-01','YYYY-MM-DD')),
nvl(col2,TO_DATE('2901-01-01','YYYY-MM-DD')),
nvl(col3,TO_DATE('2901-01-01','YYYY-MM-DD')),
nvl(col4,TO_DATE('2901-01-01','YYYY-MM-DD'))
)
= TO_DATE('2901-01-01','YYYY-MM-DD')
then null
else
least
(
nvl(col1,TO_DATE('2901-01-01','YYYY-MM-DD')),
nvl(col2,TO_DATE('2901-01-01','YYYY-MM-DD')),
nvl(col3,TO_DATE('2901-01-01','YYYY-MM-DD')),
nvl(col4,TO_DATE('2901-01-01','YYYY-MM-DD'))
)
end
as min_date
from tbl
If a id column in your table. Then
Query
select t.id, min(t.col) as min_col_value from(
select id, col1 as col from your_table
union all
select id, col2 as col from your_table
union all
select id, col3 as col from your_table
union all
select id, col4 as col from your_table
)t
group by t.id;
If you want the first date, then use coalesce():
select coalesce(col1, col2, col3, col4)
from t;
This returns the first non-NULL value (which is one way that I interpret the question). This will be the minimum date, if the dates are in order.
Select Id, CaseWhen (Col1 <= Col2 OR Col2 is null) And (Col1 <= Col3 OR Col3 is null) Then Col1 When (Col2 <= Col1 OR Col1 is null) And (Col2 <= Col3 OR Col3 is null) Then Col2 Else Col3 End As Min From YourTable
This is for 3 Column, Same way you can write for 4 - or more column.
I think I have a misunderstanding of how NOT EXISTS work and hope it can be clarified to me.
Here is the sample code I am running (also on SQL Fiddle)
select sum(col1) col1, sum(col2) col1, sum(col3) col3
from (
select 1 col1, 1 col2, 1 col3
from dual tbl1
)
where not exists(
select 2 col1, 1 col2, 1 col3
from dual tbl2
)
I thought that it should return:
1, 1, 1
But instead it returns nothing.
I make this assumption only on the fact that I though NOT EXISTS would give me a list of all the rows in the first query that do not exist in the second query (in this case 1,1,1)
Why does this not work
What would be the appropriate way to make it work the way I am expecting it to?
You are performing an uncorrelated subquery in your NOT EXISTS() condition. It always returns exactly one row, therefore the NOT EXISTS condition is never satisfied, and your query returns zero rows.
Oracle has a rowset difference operator, MINUS, that should do what you wanted:
select sum(col1) col1, sum(col2) col1, sum(col3) col3
from (
select 1 col1, 1 col2, 1 col3
from dual tbl1
MINUS
select 2 col1, 1 col2, 1 col3
from dual tbl2
)
SQL Server has an EXCEPT operator that does the same thing as Oracle's MINUS. Some other databases implement one or the other of these.
EXISTS just returns true if a record exists in the result set; it does not do any value checking. Since the sub-query returns one record, EXISTS is true, NOT EXISTS is false, and you get no records in your result.
Typically you have a WHERE cluase in the sub-query to compare values to the outer query.
One way to accomplish what you want is to use EXCEPT:
select sum(col1) col1, sum(col2) col1, sum(col3) col3
from (
select 1 col1, 1 col2, 1 col3
from dual tbl1
)
EXCEPT(
select 2 col1, 1 col2, 1 col3
from dual tbl2
)
A not exists that includes a select from dual will never return anything. Not exists will exclude rows where the embedded SQL returns something. Normally not exists should be used more like this:
select ... from MY_TABLE A where not exists (select 1 from OTHER_TABLE B where A.SOME_COL = B.SOME_COL)
As using NOT EXISTS is not good approach as it is return only single row so try it with MINUS or EXCEPT
select sum(col1) col1, sum(col2) col1, sum(col3) col3 from ( select 1 col1, 1 col2, 1 col3 from dual tbl1 MINUS select 2 col1, 1 col2, 1 col3 from dual tbl2 )
select sum(col1) col1, sum(col2) col1, sum(col3) col3 from ( select 1 col1, 1 col2, 1 col3 from dual tbl1 ) EXCEPT( select 2 col1, 1 col2, 1 col3 from dual tbl2 )