I have:
Table id
+--------+
| number |
+--------+
| 1 |
| 2 |
| 3 |
+--------+
Table data
+-------+--------------+
| name | phone_number |
+-------+--------------+
| Bob | 111 |
| John | 333 |
| Alice | 555 |
+-------+--------------+
How to join table with results: (number from minimum value & name='John') ?
+--------+-------+--------------+
| number | name | phone_number |
+--------+-------+--------------+
| 1 | John | 333 |
+--------+-------+--------------+
You can try below -
select
(select min(number) FROM ID) as number, name, phone_number
from date
where name = 'John'
You can use cross join:
select min(number) as number, name, phone_number
from Table_Id
cross join Table_Data
group by name, phone_number
Depending on the RDBMS you're using, this query should get you close.
SELECT
MIN_NUMBER, NAME, PHONE_NUMBER
FROM
DATA LEFT JOIN (SELECT MIN(NUMBER) AS MIN_NUMBER FROM ID) ON 1=1
WHERE NAME = 'JOHN'
Related
I have the following table (simplified from the real table) at the moment:
+----+-------+-------+
| ID | Name | Phone |
+----+-------+-------+
| 1 | Tom | 123 |
| 1 | Tom | 123 |
| 1 | Tom | 123 |
| 2 | Mark | 321 |
| 2 | Mark | 321 |
| 3 | Kate | 321 |
+----+-------+-------+
My desired output in the SELECT statement is:
+----+------+-------+
| ID | Name | Phone |
+----+------+-------+
| 2 | Mark | 321 |
| 3 | Kate | 321 |
+----+------+-------+
I want to select duplicates only when they occur between two different IDs (like Mark and Kate sharing the same phone number), but not to show any records for IDs that share the same phone number with themselves only (like Tom).
Could someone advise how this can be achieved?
You can use an EXISTS condition with a correlated subquery to ensure that another record exists that has the same phone and a different id. We also need DISTINCT to remove the duplicates in the resultset.
SELECT DISTINCT id, name, phone
FROM mytable t
WHERE EXISTS (
SELECT 1
FROM mytable t1
WHERE t1.phone = t.phone AND t1.id <> t.id
)
Demo on DB Fiddle:
| id | name | phone |
| --- | ---- | ----- |
| 2 | Mark | 321 |
| 3 | Kate | 321 |
You can use window functions for this:
select t.*
from (select t.*,
row_number() over (partition by phone, name order by id) as seqnum,
min(id) over (partition by phone) as min_id,
max(id) over (partition by phone) as max_id
from t
) t
where seqnum = 1 and min_id <> max_id;
Another method uses aggregation and a window function:
select phone, name, id
from (select phone, name, id,
count(*) over (partition by phone) as num_ids
from t
group by phone, name, id
) pn
where num_ids > 1;
Both of these have the advantage over the exists solution (GMB's) that they refer to the "table" only once. That can be a big advantage if the table is a complex view or query. If performance is an issue, I would encourage you to test several variants to see which works best.
Can use somewhat a corelated query with group by and having as below
Select ID, NAME, max(PHONE) From
(Select * From Table) t group by id,
name having
1= max(
case
When phone in (select phone from
table where t.id<>Id) then 1 else 0)
end)
I am trying to identify the count of each distinct value in one column (name) in a table called brgy.
---------------------
| ID | name |
---------------------
| 1 | Alfonso |
| 2 | Arakan |
| 3 | Poblacion |
| 4 | Ilaya |
| 5 | Poblacion |
----------------------
I tried using this code but it keeps giving the COUNT as 1 despite Poblacion appearing twice in the name column:
SELECT name,COUNT(name) AS distinct_name
FROM (
SELECT DISTINCT name
FROM brgy
GROUP BY name
)
GROUP BY name;
The intended output should eliminate duplicate names but sum up the number of times the distinct name appears in the name column:
Expected Output is as below,
-----------------------------
| name | distinct_name |
-----------------------------
| Alfonso | 1 |
| Arakan | 1 |
| Ilaya | 1 |
| Poblacion | 2 |
-----------------------------
A simple GROUP BY name:
SELECT name, COUNT(name) AS distinct_name
FROM brgy
GROUP BY name;
you don't need the subquery:
SELECT DISTINCT name FROM brgy GROUP BY name
because GROUP BY name takes care of it.
Just removed the subquery because it will give you unique entry :
select name, count(*) as distinct_name
from brgy
group by name
order by distinct_name, name;
I have an interesting query I need to execute. For Table A below, I want to select ALL non null phoneNumber for distinct userId, but if a non null phoneNumber value doesn't exist for distinct userId select only one null phoneNumber for distinct userId.
Table A
| id | userId | phoneNumber | emailAddress |
-------------------------------------------
| 1 | 1 | 0123456789 | null |
| 2 | 1 | 1234567890 | null |
| 3 | 1 | null | test#gmail |
| 4 | 2 | null | andy#yahoo |
| 5 | 2 | null | andy#gmail |
Expected Results
| id | userId | phoneNumber | emailAddress |
-------------------------------------------
| 1 | 1 | 0123456789 | null |
| 2 | 1 | 1234567890 | null |
| 5 | 2 | null | andy#gmail |
I wrote the query below and it returns the desired results, but I'm interested to see if there is a better, more optimal way to achieve this. Rather than writing multiple subqueries.
SELECT *
FROM A
WHERE phoneNumber IS NOT NULL
UNION
SELECT *
FROM A
WHERE id IN (SELECT MAX(id)
FROM A WHERE phoneNumber IS NULL
AND userId NOT IN (SELECT userId
FROM A
WHERE phoneNumber IS NOT NULL)
GROUP BY userId)
You can use the COUNT() and ROW_NUMBER() analytic functions:
SELECT *
FROM (
SELECT A.*,
COUNT( phoneNumber) OVER ( PARTITION BY userId ) AS ct,
ROW_NUMBER() OVER ( PARTITION BY userId ORDER BY id DESC ) AS rn
FROM A
)
WHERE phoneNumber IS NOT NULL
OR ( ct = 0 AND rn = 1 );
I got those two tables sport and student:
First table sport:
|idsport | name |
_______________________
| 1 | bobsled |
| 2 | skating |
| 3 | boarding |
| 4 | iceskating |
| 5 | skiing |
Second table student:
foreign key
|idstudent | name | sport_idsport
__________________________________________
| 1 | john | 3 |
| 2 | pauly | 2 |
| 3 | max | 1 |
| 4 | jane | 2 |
| 5 | nico | 5 |
so far i did this it output which number is mostly inserted, but cant get it to work
with two tables
SELECT sport_idsport
FROM (SELECT sport_idsport FROM student GROUP BY sport_idsport ORDER BY COUNT(*) desc)
WHERE ROWNUM<=1;
I need to output name of most popular sport, in that case it would be skating.
I use oracle sql.
with counter as (
Select sport_idsport,
count(*) as cnt,
dense_rank() over (order by count(*) desc) as rn
from student
group by sport_idsport
)
select s.*, c.cnt
from sport s
join counter c on c.sport_idsport = s.idsport and c.rn = 1;
SQLFiddle example: http://sqlfiddle.com/#!4/b76e21/1
select cnt, sport_idsport from (
select count(*) cnt, sport_idsport
from student
group by sport_idsport
order by count(*) desc
)
where rownum = 1
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