I am trying to update a column in a record to true to indicate that the record is the one active in the table. However, by updating this record, I must then update all other records for that column to false. Is there a way to do this in one SQL statement? I can do it in two statements like this:
UPDATE My_Table
SET is_group_active = 0
UPDATE My_Table
SET is_group_active = 1
WHERE group_id = 2;
You could use a case expression:
UPDATE my_table
SET is_group_active = CASE group_id WHEN 2 THEN 1 ELSE 0 END;
I would write this as:
UPDATE t
SET is_group_active = (CASE group_id WHEN 2 THEN 1 ELSE 0 END)
WHERE is_group_active <> (CASE group_id WHEN 2 THEN 1 ELSE 0 END);
Or perhaps:
UPDATE t
SET is_group_active = (CASE group_id WHEN 2 THEN 1 ELSE 0 END)
WHERE is_group_active = 1 OR group_id = 2
There is no need to update rows that already have the correct value. (Note: The logic would be slightly more complicated if is_group_active can take on NULL values).
Related
I have TableA with the following data
Name A B Final
Andy 1 1 2
Sam 1 0 2
I want to write an update query which will do the following:
If sum(A+B) <> Final then update row else do not Update
My Query
Update TableA
Set A = Case when Final in (1,2) then 1 else 0 End
Set B = Case When Final = 2 then 1 else 0
where final in (1,2) and **final <> sum(A+B)**
Since we can't use an aggregate function in update where clause I am not sure how to do the last part.
The query should only update row for Sam.
Thanks for you help!
Update TableA
Set A = Case when Final in (1,2) then 1 else 0 End
Set B = Case When Final = 2 then 1 else 0
where final in (1,2) and final <> A+B
How do I change the following code to an if statement that returns a boolean 0 or 1 value? My end results I would like to have, is one column listing the interest rate of 2, and my results column with a 0 or 1 if the condition is true.
(Case when new_interestratevariability = 2
and (new_interestrateindex = 1 or new_interestrateindex = 2 or new_interestrateindex = 3 or new_interestrateindex = 4 or new_interestrateindex = 6)
and new_crms_dt = #Curr_Date
then 0 else 1 end) as CIEDIT_VAL_96,
Currently, I am getting something like below:
Results Table
To filter rows, use a Where clause. The Case statement in the Select clause will modify the value shown on the row.
Select *
from table
Where new_interestratevariability = 2
and new_interestrateindex IN (1,2,3,4,6)
and new_crms_dt = #Curr_Date
Found my answer, it was as simple as adding "not in" instead of just "in". Thanks everyone
(Case when new_interestratevariability = 2
and (new_interestrateindex not in(1,2,3,4,6))
and new_crms_dt = #Curr_Date
then 1 else 0 end) as CIEDIT_VAL_96,
i have a simple problem. i have a column with numbers. i need to filter them to even and odd numbers, but if a number is even than i need to copy or move it to "even-number-column" in the same table. if the number is odd then move it to "odd-number-column" in the same table.
this is my code:
select distinct all_numbers, even-number-column, odd-number-column
case when all_numbers%2=0
then UPDATE my_table SET even-number-column = all_numbers
else UPDATE my_table SET odd-number-column = all_numbers
end
from my_table ;
If you want a SELECT:
select
distinct all_numbers,
CASE
WHEN when all_numbers%2 = 0 THEN all_numbers
ELSE 0 -- or NULL
END as even-number-column,
CASE
WHEN when all_numbers%2 = 1 THEN all_numbers
ELSE 0 -- or NULL
END as odd-number-column
from my_table ;`
If you want an update
UPDATE my_table
SET
even-number-column = CASE
WHEN when all_numbers%2 = 0 THEN all_numbers
ELSE even-number-column -- or change for 0 or NULL
END,
odd-number-column = CASE
WHEN when all_numbers%2 = 1 THEN all_numbers
ELSE odd-number-column -- or change for 0 or NULL
END
Use an array to make it simple
update t
set
odd = (array[null, all_numbers])[all_numbers % 2 + 1],
even = (array[all_numbers, null])[all_numbers % 2 + 1]
I have a table with 3 columns (containing Integer values that assume only values from 0 to 10). I want extract, with a single query, a table with 1 column. This column must assume a value based on the following logic:
If one of these three columns has value 0 ----> the value of column of table generated by query must be 0 too.
If none of the last three columns has value 0 ----> the value of column must assume the value 1.
You are looking for CASE construct or IF function:
SELECT CASE WHEN (t.field1 = 0 OR t.field2 = 0 OR t.field3 = 0) THEN 0
ELSE 1 END AS value
FROM t;
In this specific case you might also use the fact that any member being zero will zero the product:
SELECT CASE WHEN (t.field1*t.field2*t.field3 = 0) THEN 0 ELSE 1 END AS value
FROM t;
Or
SELECT IF((t.field1*t.field2*t.field3)=0, 0, 1) AS value FROM t;
This is a simple case statement. Assuming there are no NULL values, try this:
select (case when col1 = 0 or col2 = 0 or col3 = 0 then 0 else 1 end)
Try this
SELECT
CASE
WHEN column1 = 0 THEN 0
WHEN column2 = 0 THEN 0
WHEN column3 = 0 THEN 0
ELSE 1
END
FROM urtable
I need to set a query like below:
UPDATE XXXXXX
IF column A = 1 then set column B = 'Y'
ELSE IF column A = 2 then set column C = 'Y'
ELSE IF column A = 3 then set column D = 'Y'
and so on and so forth...
I am able to do this using multiple queries but was wondering, if I can do it in just 1 statement instead.
this should work
update table_name
set column_b = case
when column_a = 1 then 'Y'
else null
end,
set column_c = case
when column_a = 2 then 'Y'
else null
end,
set column_d = case
when column_a = 3 then 'Y'
else null
end
where
conditions
the question is why would you want to do that...you may want to rethink the data model. you can replace null with whatever you want.
Yes you can use CASE
UPDATE table
SET columnB = CASE fieldA
WHEN columnA=1 THEN 'x'
WHEN columnA=2 THEN 'y'
ELSE 'z'
END
WHERE columnC = 1