My current table:
id | count | group_id
1 1 employee
2 2 employee
3 3 employee
4 4 employee
What I want:
id | count | group_id
1 4 employee
2 3 employee
3 2 employee
4 1 employee
What i've attempted
UPDATE table SET count = 4 WHERE count = 1 AND group_id='employee';
UPDATE table SET count = 3 WHERE count = 2 AND group_id='employee';
UPDATE table SET count = 2 WHERE count = 3 AND group_id='employee';
UPDATE table SET count = 1 WHERE count = 4 AND group_id='employee';
For obvious reason this does not work because it executes each query row by row, so my result is wrong. I think i'm looking for a way of updating multiple tables with one query?
This specific case can be solved like this:
UPDATE table SET count = 5 - count
WHERE count between 1 and 4 AND group_id= 'employee';
A more general solution, use a CASE expression:
UPDATE table SET count = case count when 4 then 1
when 3 then 2
when 2 then 3
when 1 then 4
end
WHERE count between 1 and 4 AND group_id = 'employee';
Related
There is a table with values as below,
Id Value
1 1
2 1
3 2
4 2
5 3
6 4
7 4
now need to write a query to retrieve value from the table and output should look as
ID Value
1 1
3 2
5 3
6 4
any suggestion ?
The query you want is nothing to do with being distinct, it's a simple aggregation of value with the minimum ID for each:
select Min(id) Id, value
from table
group by value
I have following tables.
Part
id
name
1
Part 1
2
Part 2
3
Part 3
Operation
id
name
part_id
order
1
Op 1
1
10
2
Op 2
1
20
3
Op 3
1
30
4
Op 1
2
10
5
Op 2
2
20
6
Op 1
3
10
Lot
id
part_id
Operation_id
10
1
2
11
2
5
12
3
6
I am selecting the results from Lot table and I want to select a column last_Op which is based on the order value of the operation_id. If value of order for the operation_id is the highest for the respective part_id, return 1 else return 0
SELECT
id,
part_id,
operation_id,
last_Op
FROM Lot
expected result set based on the tables above.
id
part_id
operation_id
last_op
10
1
2
0
11
2
5
1
12
3
6
1
In above example, first row returns last_op = 0 because operation_id = 2 is associated with part_id = 1 and it has the highest order = 30. Since operation_id for this part is not pointing towards the highest order value, 0 is returned.
The other two rows return 1 because operation_id 5 and 6 are associated with part_id 2 and 3 respectively and they are pointing towards the highest 'order' value.
If value of order for the operation_id is the highest for the respective part_id, return 1 else return 0
This sounds like window functions will help:
select l.*,
(case when o.order = o.max_order then 1 else 0 end) as last_op
from lot l left join
(select o.*,
max(o.order) over (partition by o.part_id) as max_order
from operations o
) o
on l.operation_id = o.id;
Note: order is a very poor name for a column because it is a SQL keyword.
I have this table my_table_c with the below values
SELECT * FROM my_table_c
ID GROUP_ID GROUP_VALUE
1 2 1
3 3 2
3 4 1
5 4 1
5 2 1
2 2 2
2 3 2
2 4 1
I am looking for this output where I get only the ID which do not have group_id 2. Additionally, I don't want to get the ID where group_id 2 is absent but other group ids are present.
If group_id 2 is absent, that's my target id.
So with the values shown in table above, I just expect ID = 3 to be returned as other ids 1, 5 and 2 each have rows where group_id = 2.
Can anyone please help with a query to fetch this result.
You could get all the id's that have group_id = 2 and use NOT IN
select *
from my_table_c
where id not in (select id from my_table_c where group_id = 2)
Another way but using NOT EXISTS
select *
from my_table_c mtcA
where not exists (select *
from my_table_c mtcB
where mtcA.id = mtcB.id and mtcB.group_ID = 2)
I have following tables in APEX A and B.
A has columns:
ID_A;
VALUE;
B has columns:
ID_C_FK;
ID_A_FK
I want to update the VALUE column in table A in rows where ID_A equals ID_A_FK in selected rows from table B where ID_C_FK equal x
For example: A has rows (
ID_A value
------------
1 1
2 1
3 0
4 0
5 0
Table B has rows
ID_C_FK ID_A_FK
------------------
8 4
9 4
9 5
I want to update VALUE in table A only for those rows that have ID_A in rows selected from B and condition to select rows from B is that ID_C_FK equals x = 9; and as a result, table A should end up having rows:
ID_A value
------------
1 1
2 1
3 0
4 1
5 1
How to write such update in PL/SQL?
Thank you for considering my request.
I think this is what you want:
update a
set value = 1
where exists (select 1
from b
where b.id_a_fk = a.id_a and b.id_c_fk = 9
);
I'm trying to create an SQL statement to match either an id number or a postcode and then assign a new id number
What I want to end up with is ‘newid’ that correctly recognizes that the first four records are the same person (even though the postcode for record 2 is different).
record id postcode newid
--------------------------
1 1 1 1
2 1 2 1
3 1 1 1
4 2 1 1
5 3 3 2
Any suggestions would be appreciated greatly.
Going based on your example:
SELECT RECORD,
(SELECT MIN (ID)
FROM users u2
WHERE users.id IN (u2.id, u2.postcode)
OR users.postcode in (u2.id, u2.postcode)
) AS newid
FROM users
This results with the following data:
RECORD NEWID
------------------
1 1
2 1
3 1
4 1
5 3
Here is the SQLFiddle