(query access)
This is the table structure:
+-----+--------+--------+
| id | name | sub1 |
+-----+--------+--------+
| 1 | ABC | 6.27% |
| 2 | ABC | 7.47% |
| 3 | PQR | 3.39% |
| 4 | PQR | 2.21% |
+-----+--------+--------+
I want to subtract Sub1
Output should be:
+-----+--------+---------+------------------------------------+
| id | name | sub1 | |
+-----+--------+---------+------------------------------------+
| 1 | ABC | 6.27% | 0 First Rec no need Subtract |
| 2 | ABC | 7.47% | 1.2% <=(7.47-6.27) |
| 3 | PQR | 3.39% | 0 First Rec no need Subtract |
| 4 | PQR | 2.21% | -1.18% <=(2.21-3.39) |
+-----+--------+---------+------------------------------------+
Thank you so much.
If you can guarantee consecutive id values, then the following presents an alternative:
select t.*, nz(t.sub1-u.sub1,0) as sub2
from YourTable t left join YourTable u on t.name = u.name and t.id = u.id+1
Change YourTable to the name of your table.
This is painful, but you can do:
select t.*,
(select top 1 t2.sub1
from t as t2
where t2.name = t.name and t2.id < t.id
order by t2.id desc
) as prev_sub1
from t;
This gives the previous value or NULL for the first row. You can just use - for the subtraction.
An index on (name, id) would help a bit with performance. However, if you can upgrade to a better database, you can then just use lag().
Related
I have two tables Table 1 and Table 2
Table 1:
-------------------------------
| Ser | StartDate | Activity |
-------------------------------
| 1 | 2002-10-13 | 1 |
| 1 | 2002-10-13 | 2 |
| 1 | 2007-09-04 | 3 |
Table 2:
------------------------
|Ser|DateOfRegistration|
------------------------
| 1 | 2002-10-12 |
| 1 | 2007-09-02 |
Now, the result that I want is such that for Activity 1 and 2 the Date of registration should be before the Start Date and difference between the dates must be the least. Similarly, for Activity 3, the date of registration for Activity 3 should be before the start date. The result should look like this.
Table 3:
--------------------------------------------
|Ser|StartDate |DateofRegistration|Activity|
--------------------------------------------
| 1 |2002-10-13| 2002-10-12 | 1 |
| 1 |2002-10-13| 2002-10-12 | 2 |
| 1 |2002-09-04| 2002-09-02 | 3 |
How can I join Table 1 and 2 to get Table 3?
You can use outer apply:
select t1.*, t2.dateofregistration
from table1 t1 outer apply
(select top (1) t2.*
from table2 t2
where t2.ser = t1.ser and t2.dateofregistration < t1.startdate
order by t2.dateofregistration desc
) t2
I am having a table having records like this:
+------+------+
| ID | name |
+------+------+
| 1 | A |
| 2 | B |
| 3 | C |
| 4 | A |
| 5 | B |
| 6 | A |
| 7 | A |
| 8 | A |
+------+------+
I need to get value of A after it was last updated from a different value, for example here it would be the row at ID 6.
Try this query (MySQL syntax):
select min(ID)
from records
where name = 'A'
and ID >=
(
select max(ID)
from records
where name <> 'A'
);
Illustration:
select * from records;
+------+------+
| ID | name |
+------+------+
| 1 | A |
| 2 | B |
| 3 | C |
| 4 | A |
| 5 | B |
| 6 | A |
| 7 | A |
| 8 | A |
+------+------+
-- run query:
+---------+
| min(ID) |
+---------+
| 6 |
+---------+
Using the Lag function...
SELECT Max([ID])
FROM (SELECT [name], [ID],
Lag([name]) OVER (ORDER BY [ID]) AS PrvVal
FROM tablename) tbl
WHERE [name] = 'A'
AND prvval <> 'A'
Online Demo: http://www.sqlfiddle.com/#!18/a55eb/2/0
If you want to get the whole row, you can do this...
SELECT Top 1 *
FROM (SELECT [name], [ID],
Lag([name]) OVER (ORDER BY [ID]) AS PrvVal
FROM tablename) tbl
WHERE [name] = 'A' AND prvval <> 'A'
ORDER BY [ID] DESC
Online Demo: http://www.sqlfiddle.com/#!18/a55eb/22/0
The ANSI SQL below uses a self-join on the previous id.
And the where-clause gets those with a name that's different from the previous.
select max(t1.ID) as ID
from YourTable as t1
left join YourTable as t2 on t1.ID = t2.ID+1
where (t1.name <> t2.name or t2.name is null)
and t1.name = 'A';
It should work on most RDBMS, including MS Sql Server.
Note that with the ID+1 that there's an assumption that are no gaps between the ID's.
I have two tables:
Table #1 - Student:
+------+-------+
|Roll | Name |
+------+-------+
| 1 | A |
| 2 | B |
| 3 | C |
+------+-------+
Table #2 - Mark:
+------+------+
| Roll | Mark |
+------+------+
| 1 | 85 |
| 3 | 95 |
+------+------+
Output needs to be:
+-------+------+-------+---------+
| Roll | Name | Mark |Position |
+-------+------+-------+---------+
| 1 | A | 85 | 2 |
| 2 | B | 0 | 3 |
| 3 | C | 95 | 1 |
+-------+------+-------+---------+
What should be the query to get the output? I think the rank function is to be used, but don't know to use it...
Use LEFT JOIN to join two tables and then use RANK().
Query
select *, Position = rank() over(
order by t.Mark desc
)
from(
select t1.Roll, t1.Name, coalesce(t2.Mark, 0) as Mark
from student t1
left join Mark t2
on t1.Roll = t2.Roll
)t
order by t.Name;
Use Left Join and Rank() function.
Query
select T1.Roll, T1.Name, isnull(T2.Mark,0) Mark, rank() over(order by mark desc) Position
from STUDENT T1 left join MARK T2
on T1.Roll = T2.Roll order by T1.Roll
I have to get a specific output format from my tables.
Let's say I have a simple table with 2 columns name and value.
table T1
+---------------+------------------+
| Name | Value |
+---------------+------------------+
| stuff1 | 1 |
| stuff1 | 1 |
| stuff2 | 2 |
| stuff3 | 1 |
| stuff2 | 4 |
| stuff2 | 2 |
| stuff3 | 4 |
+---------------+------------------+
I know the values are in the interval 1-4. I group it by name and value and count number of the same rows as Number and get the following table:
table T2
+---------------+------------------+--------+
| Name | Value | Number |
+---------------+------------------+--------+
| stuff1 | 1 | 2 |
| stuff2 | 2 | 2 |
| stuff3 | 1 | 1 |
| stuff3 | 4 | 1 |
+---------------+------------------+--------+
Here is the part when I need your help! What should I do if I want to get these format?
table T3
+---------------+------------------+--------+
| Name | Value | Number |
+---------------+------------------+--------+
| stuff1 | 1 | 2 |
| stuff1 | 2 | 0 |
| stuff1 | 3 | 0 |
| stuff1 | 4 | 0 |
| stuff2 | 1 | 0 |
| stuff2 | 2 | 2 |
| stuff2 | 3 | 0 |
| stuff2 | 4 | 0 |
| stuff3 | 1 | 1 |
| stuff3 | 2 | 0 |
| stuff3 | 3 | 0 |
| stuff3 | 4 | 1 |
+---------------+------------------+--------+
Thanks for any suggestions!
You start with a cross join to generate all possible combinations and then left-join in the results from your existing query:
select n.name, v.value, coalesce(nv.cnt, 0) as "Number"
from (select distinct name from table t) n cross join
(select distinct value from table t) v left outer join
(select name, value, count(*) as cnt
from table t
group by name, value
) nv
on nv.name = n.name and nv.value = v.value;
Variation on the theme.
Differences between Gordon Linoff and Owen existing answers.
I prefer GROUP BY to get the Names rather than a DISTINCT. This may have better performance in a case like this. (See Rob Farley's still relevant article.)
I explode the subqueries into a series of CTEs for clarity.
I use table T2 as the question now labels the group results set instead of showing that as as subquery.
WITH PossibleValue AS (
SELECT 1 Value
UNION ALL
SELECT Value + 1
FROM PossibleValue
WHERE Value < 4
),
Name AS (
SELECT Name
FROM T1
GROUP BY Name
),
NameValue AS (
SELECT Name
,Value
FROM Name
CROSS JOIN
PossibleValue
)
SELECT nv.Name
,nv.Value
,ISNULL(T2.Number,0) Number
FROM NameValue nv
LEFT JOIN
T2 ON nv.Name = T2.Name
AND nv.Value = T2.Value
Yet another solution, this time using a Table Value Constructor in a CTE to build a table of name value combinations.
WITH value AS
( SELECT DISTINCT t.name, v.value
FROM T1 AS t
CROSS JOIN (VALUES (1),(2),(3),(4)) AS v (value)
)
SELECT v.name AS 'Name', v.value AS 'Value', COUNT(t.name) AS 'Number'
FROM value AS v
LEFT JOIN T1 AS t ON t.value = v.value AND t.name = v.name
GROUP BY v.name, v.value, t.name;
given below table:
+----+---------+-----------+-------------+-------+
| ID | NAME | LAST NAME | PHONE | STATE |
+----+---------+-----------+-------------+-------+
| 1 | James | Vangohg | 04333989878 | NULL |
| 2 | Ashly | Baboon | 09898788909 | NULL |
| 3 | James | Vangohg | 04333989878 | NULL |
| 4 | Ashly | Baboon | 09898788909 | NULL |
| 5 | Michael | Foo | 02933889990 | NULL |
| 6 | James | Vangohg | 04333989878 | NULL |
+----+---------+-----------+-------------+-------+
I want to use MS SQL to find and update duplicate (based on name, last name and number) but only the earlier one(s). So desired result for above table is:
+----+---------+-----------+-------------+-------+
| ID | NAME | LAST NAME | PHONE | STATE |
+----+---------+-----------+-------------+-------+
| 1 | James | Vangohg | 04333989878 | DUPE |
| 2 | Ashly | Baboon | 09898788909 | DUPE |
| 3 | James | Vangohg | 04333989878 | DUPE |
| 4 | Ashly | Baboon | 09898788909 | NULL |
| 5 | Michael | Foo | 02933889990 | NULL |
| 6 | James | Vangohg | 04333989878 | NULL |
+----+---------+-----------+-------------+-------+
This query uses a CTE to apply a row number, where any number > 1 is a dupe of the row with the highest ID.
;WITH x AS
(
SELECT ID,NAME,[LAST NAME],PHONE,STATE,
ROW_NUMBER() OVER (PARTITION BY NAME,[LAST NAME],PHONE ORDER BY ID DESC)
FROM dbo.YourTable
)
UPDATE x SET STATE = CASE rn WHEN 1 THEN NULL ELSE 'DUPE' END;
Of course, I see no reason to actually update the table with this information; every time the table is touched, this data is stale and the query must be re-applied. Since you can derive this information at run-time, this should be part of a query, not constantly updated in the table. IMHO.
Try this statement.
LAST UPDATE:
update t1
set
t1.STATE = 'DUPE'
from
TableName t1
join
(
select name, last_name, phone, max(id) as id, count(id) as cnt
from
TableName
group by name, last_name, phone
having count(id) > 1
) t2 on ( t1.name = t2.name and t1.last_name = t2.last_name and t1.phone = t2.phone and t1.id < t2.id)
If my understanding of your requirements is correct, you want to update all of the STATE values to DUPE when there exists another row with a higher ID value that has the same NAME and LAST NAME. If so, use this:
update t set STATE = (case when sorted.RowNbr = 1 then null else 'DUPE' end)
from yourtable t
join (select
ID,
row_number() over
(partition by name, [last name], phone order by id desc) as RowNbr from yourtable)
sorted on sorted.ID = t.ID