This is table structure
id
1
2
3
4
5
6
I need result like this
id even odd
1 0 1
2 1 0
3 0 1
4 1 0
5 0 1
6 1 0
I tried
select id %2=0 then 1 else 0 end or id%2 <>0 then 1 else 0 odd
from table
How about
select
id,
~id & 1,
id & 1
from t
Take a look at the CASE keyword. It works very similarly to what you're trying to do in your SELECT statement. In addition, if you want to select multiple columns, separate them with a comma. The OR keyword is used for combining logical conditions in your query, not for specifying multiple columns.
An example of how you could use CASE in your query would be as follows:
SELECT id,
CASE WHEN id %2=0 THEN 1 ELSE 0 END AS Even,
[column2]
FROM [TableName]
The table structure is just Id?
you could try this!
select *,
case when id %2=0 then 1 else 0 end as even,
case when id %2 <>0 then 1 else 0 end as odd
from table
You have the right idea, but your syntax is a bit off. I'd use a CASE statement to create the even column, and then a calculate odd accordingly:
SELECT id, even, ABS(even - 1) AS odd
FROM (SELECT id, CASE WHEN id % 2 = 0 THEN 1 ELSE 0 END AS even
FROM my_table)
Related
I have 2 tables: Entity and EntityItem.
EntityItems table has a Reason column which is nullable enum.
I'm trying to write a view that would return some Entititys columns and additionally a boolean column that states whether all corresponding EntityItem.Reason have a non-null value.
The following query returns somewhat what I want:
SELECT EntityItem.Id, COUNT(EntityItem.Reason) As Test
FROM EntityItem
GROUP BY EntityItem.ParentEntityId
ORDER BY Test DESC
Example output:
Id Test
132189 4
132190 2
132197 1
1 0
2 0
3 0
4 0
5 0
6 0
However, when I try to add this to a final query I get duplicated lines for each EntityItem
SELECT [Entity].[Id],
...
(SELECT CASE WHEN (SELECT COUNT([EntityItem].[Reason]) FROM [EntityItem] WHERE [EntityItem].[ParentEntityId] = [Entity].[Id]) = 0
THEN 0
ELSE 1
END) AS Test
FROM [Entity]
...
LEFT JOIN [EntityItem] ON [Entity].[Id] = [EntityItem].[ParentEntityId]
Example output:
Id Test
1 1
1 1
2 0
2 0
2 0
2 0
3 1
3 1
4 0
Question 1: Is my approach correct?
Question 2: Is there a way to remove duplicated lines without DISTINCT?
For your second query you need to aggregate before joining, for example by using outer apply something like:
select e.Id,
case when i.cnt = 0 then 0 else 1 end as Test
from Entity e
outer apply (
select Count(Reason) cnt
from EntityItem i
where i.ParentEntityId = e.Id
)i;
Saying that, since you are always returning a value of 1 if the count is greater than zero you don't actually need to count anything:
select e.Id,
case when exists (
select * from EntityItem i
where i.ParentEntityId = e.Id
)
then 1 else 0 end as Test
from Entity e;
In one of the usecase I need a query which should return 1 based on condition also if not match it should return 0
In Descpriont column if the 'SAP' count is exactly 1 then the query should return 1 else it should return 0
Note : There might be a chance that SAP could be present any number of times in Description column.
Could someone help me out here !!
Thanks.
I tried below query :
SELECT 1 from TableName where Description ='SAP' having count(*)>1
It is returning 1 but not return 0 if the count is more than 1 or no match found.
Use CASE WHEN to decide whether to show 0 or 1.
select case when count(*) = 1 then 1 else 0 end as sap_count_is_1
from mytable
where description = 'SAP';
use case when
select
case when sum(case when description='SAP' then 1 else 0 end)=1 then 1 else 0 end from table_name
I have a SQL query like so
SELECT
name,
CASE WHEN (new_value=2) THEN 0 END as out,
CASE WHEN (previous_value=2) THEN 1 END as out
FROM my_table;
This results in duplicate columns:
name out out
foo 1 null
bar null 1
instead of
name out
foo 1
bar 0
How do I fix this?
You want one case expression with two conditions:
SELECT name,
(CASE WHEN new_value = 2 THEN 0
WHEN previous_value = 2 THEN 1
END) as out
FROM my_table;
Consider:
SELECT
name,
CASE
WHEN new_value = 2 THEN 0
WHEN previous_value = 2 THEN 1
END as out
FROM my_table;
In your query, each case expression generates one column in the resulset. You want only one, with two branches (denoted by when ... then ...)
You are getting null output, so you need to add else on this.
select name,
case
when new_value = 2 then 0
when previous_value = 2 then 1
else 0 end as out
from my_table;
I had a query where i am trying to get the results of a query, the query can have multiple rows or it can be empty, i am trying if it is empty, it should return me 0 for a column i am looking which is called as sequence
My query is like this:
select CASE WHEN COUNT(1) > 0 THEN 1 ELSE 0 END AS Sequence
from dbo.mytable
it returns me the either 1 or 0, for 1 i want that column should return me values or it should combine all the rows and return me the value of that column as list like 1,2,3,4,5,6,7
This should work.
SELECT
CASE WHEN MY_COUNT > 0 THEN 1 ELSE 0 END AS SEQUENCE
FROM
(SELECT COUNT(*) AS MY_COUNT
FROM
DBO.MYTABLE);
If you want only one row in the result set, simply do:
select (case when count(*) > 0 then 1 else 0 end) as sequence
from mytable;
If you care at all about performance, the more efficient method is:
select (case when exists (select 1 from dbo.mytable) then 1 else 0
end) as sequence
I have to check certain rows from table and check if-else condition for each rows
TABLE: report
COLUMNS :
sl.no, count, total_count, calls
Sample Data:
sl.no count total_count calls
----------- ----------- ----------- -----------
1 2 6 4
2 2 7 5
3 4 9 3
Here i have to check if condition
if total_count > 6
select 'Y
else
select 'N'
I get correct answer for single row. If there is multiple row it can't check all, it check only last row of my table.
Use CASE expression
SELECT
*,
CASE WHEN total_count > 6 THEN 'Yes' ELSE 'N' END
FROM report
You must use CASE.It work like if-else in t-SQL. MSDN
For example:
SELECT [num],[count], [total_count], [calls], CASE WHEN [total_count] > 6 THEN 'Y' ELSE 'N' END FROM t
You could use CASE. You can read documentation.
SELECT *,
CASE WHEN total_count > 6 THEN 'Y' ELSE ' N' END
FROM Report
The SQL version of "inline if" is CASE:
SELECT
*,
CASE WHEN total_count > 6 THEN 'Y'
ELSE 'N'
END AS IsTotalCountGreaterThanSix
FROM YourTable;