Query in getting multiple duplicate rows in SQL Server - sql-server

I have 2 tables Table1 and Table2 in which I want to get the total count of duplicate rows:
Expected output:
Query tested:
SELECT
t1.name,
t1.duplicates,
ISNULL(t2.active, 0) AS active,
ISNULL(t3.inactive, 0) AS inactive
FROM
(SELECT
t1.name, COUNT(*) AS duplicates
FROM
(SELECT c.name
FROM table1 c
INNER JOIN table2 as cd on cd.id = c.id)) t1
GROUP BY
name
HAVING
COUNT(*) > 1) t1
LEFT JOIN
(SELECT c.name, COUNT(*) AS active
FROM table1 c
WHERE name IN (SELECT c.name FROM table1 c)
GROUP BY c.name AND status = 'Active'
GROUP BY name) t2 ON t1.name = t2.name
LEFT JOIN
(SELECT c.name, COUNT(*) AS inactive
FROM table1 c
WHERE name IN (SELECT c.name FROM table1 c GROUP BY c.name)
AND status = 'InActive'
GROUP BY name) t3 ON t1.name = t3.name
ORDER BY
name
It is still returning duplicate rows and I'm unable to get the id and creator column

If you would pardon subquery and left join, i'd suggest the following query:
select b.*,
count(creator) as creator_count
from
(select a.mainid,
a.name,
sum(case when a.status = "active"
then 1 else 0 end) as active_count,
sum(case when a.status = "inactive"
then 1 else 0 end) as inactive_count,
count(a.name) as duplicate_count
from table1 as a
group by a.name
having count(a.name) > 1) as b
left join table2 as c
on b.mainid = c.mainid
group by c.mainid
having count(c.creator) > 1
rather than forcing our way to join the two table directly. First, derive the information we can get from the Table1 then join it with the Table2 to get the creator count.
SQL Fiddle: http://sqlfiddle.com/#!9/4daa19e/28

Related

Join a MS SQL Server WITH statement into a Select statement

I received this answer to this question MS SQL Server Last User Logged in Multiple Clients with Multiple Users and it works great.
;with cte as
(
select
client, myuser, lastlogin,
row_number() over (partition by client order by lastlogin desc) r#
from
#mytable
)
select *
from cte
where r# = 1
How do I get this joined to a regular Select statement that selects data from other tables also?
For example:
SELECT t1.id, t2.name
FROM table1 t1
JOIN table2 t2 ON (t2.id = t1.id)
WHERE t1.id = 1
There is no restriction, you can just join a result of a cte with other tables. Cte is a subquery, but it makes your code more readable.
;with cte as(
select client,myuser,lastlogin,row_number() over(partition by client order by lastlogin desc) r#
from #mytable
)
SELECT t1.id, t2.name
FROM table1 t1
JOIN table2 t2 ON (t2.id = t1.id)
JOIN cte t3 ON (...)
WHERE t1.id = 1
This is the same as a query with cte.
SELECT t1.id, t2.name
FROM table1 t1
JOIN table2 t2 ON (t2.id = t1.id)
JOIN ( select client,myuser,lastlogin,row_number() over(partition by client order by lastlogin desc) r#
from #mytable) t3 ON (...)
WHERE t1.id = 1

SQL Server : left join - check for right table column value is null

I have a query as follows:
select --this select should always give me 1 record
tbl1.Id, tbl1.Name, tbl1.Address, tbl2.relNo,
CASE WHEN tbl3.Comments IS NOT NULL THEN 1 ELSE 0 END AS 'Required'
from
table1 tbl1
inner join
table2 tbl2 on tbl2.Id = tbl1.Id
left join -- This left join table gives me 5 records for one instance
(select
R.Id, C.Comments
from
tblC C
inner join
tblR R on R.Id = C.id) tbl3 on tbl3.Id = tbl2.Id
I want to write a CASE statement on the rows my left join is giving to check for null value as above and my final select query always return only 1 row. Is there a way to check if all five Comments Column values from my left join be checked for NULLs in the above query?
I would take a shortcut an use a COUNT() OVER PARTITION
CASE WHEN COUNT(*) OVER (PARTITION BY tbl3.Id) =0 THEN 0 ELSE 1 END AS 'Required'
You would have to DISTINCT your output above. Another option would be to GROUP BY and filter in the HAVING clause.
select --this select should always give me 1 record
tbl1.Id, tbl1.Name, tbl1.Address, tbl2.relNo
From table1 tbl1
inner join table2 tbl2 on tbl2.Id = tbl1.Id
left join (-- This left join table gives me 5 records for one instance
SELECT R.Id,
C.Comments
FROM tblC C
INNER JOIN tblR R on R.Id = C.id
) tbl3 on tbl3.Id = tbl2.Id
GROUP BY
Id, Name, Address, relNo
HAVING
COUNT(*) = 5
Is this what you're looking for?
(CASE WHEN (select count(tbl3.id) FROM tbl3 WHERE tbl3.Comments IS NULL) then 1 else 0 end) as 'RequiredVal'
select --this select should always give me 1 record
tbl1.Id, tbl1.Name, tbl1.Address, tbl2.relNo,
CASE WHEN tbl3.Comments IS NOT NULL THEN 1 ELSE 0 END AS 'Required'
, (CASE WHEN (select count(tbl3.id) FROM tbl3 WHERE tbl3.Comments IS NULL) then 1 else 0 end) as 'RequiredVal'
From table1 tbl1
inner join table2 tbl2 on tbl2.Id = tbl1.Id
left join (-- This left join table gives me 5 records for one instance
SELECT R.Id,
C.Comments
FROM tblC C
INNER JOIN tblR R on R.Id = C.id
) tbl3 on tbl3.Id = tbl2.Id

How to compare data any field of two table in SQL Server?

I have two tables with same columns.
Table A have ID, Name, Des, Status and
Table B have ID, Name, Des, Status.
I want to compare data any field of Table B with Table A, except column ID because same.
As same picture above, when FETCH data of Table B, detect data of ID ID001 and ID003 not same, idea of my mind same
IF (SELECT COUNT (SELECT * FROM TABLE A RIGHT JOIN TABLE B ON A.ID = B.ID) != 0)
BEGIN
PRINT 'BLAH BLAH, NOT SAME'
END
If you have idea or solution, share for me, Thank you so much.
You can use CHECKSUM or BINARY_CHECKSUM:
SELECT a.*, b.*
FROM TableA a INNER JOIN TableB b ON b.ID = a.ID
WHERE CHECKSUM(b.Name, b.Des, b.Status) <> CHECKSUM(a.Name, a.Des, a.Status)
See also this link. It should be faster then multiple OR conditions.
IF (SELECT COUNT(*)
FROM TableA a INNER JOIN TableB b ON b.ID = a.ID
WHERE BINARY_CHECKSUM(b.Name, b.Des, b.Status)
<> BINARY_CHECKSUM(a.Name, a.Des, a.Status)
>0
PRINT 'Not the same.'
Since it is not too much clear how do you want to show your differences, this is one approach:
SELECT A.ID,
(CASE WHEN A.Name <> B.Name THEN 'Diff Name' ELSE '') NameCompare,
(CASE WHEN A.Des <> B.Des THEN 'Diff Des' ELSE '') DESCompare,
(CASE WHEN A.Status <> B.Status THEN 'Diff Status' ELSE '') StatusCompare
FROM A
INNER JOIN B
ON A.ID = B.ID
This is a simple join
To get all different rows, you can say:
select a.*, b.*
from TableA a inner join TableB b on b.ID = a.ID
where b.Name <> a.Name or b.Des <> a.Des or b.Status <> a.Status

SubSelect Top 1 OR Left Join

I have a Select with sub selects using Top 1 and where clause.
I tried to optimize the select by doing a Left Join of the sub selects but the query time took longer. Is subselect better in this case? I couldnt post my whole select because it is too long and confidential but I will try to recreate the important part below:
Sub Select
SELECT
(select top 1 colId FROM table1 WHERE col1 = b.Id and col2 = 3 Order by 1) Id3,
(select top 1 colId FROM table1 WHERE col1 = b.Id and col2 = 5 Order by 1) Id5,
(select top 1 colId FROM table1 WHERE col1 = b.Id and col2 = 7 Order by 1) Id7
FROM table2 b
Trying it w/ Left Join
SELECT
t1.colid id3,
t2.colid id5,
t3.colid id7
FROM table2 b
LEFT JOIN (
select colId, col1 FROM table1 WHERE col2 = 3
) t1 ON t1.col1 = b.Id
LEFT JOIN (
select colId, col1 FROM table1 WHERE col2 = 5
) t2 ON t1.col1 = b.Id
LEFT JOIN (
select colId, col1 FROM table1 WHERE col2 = 7
) t3 ON t1.col1 = b.Id
Is there a better way to do this? and why is it the Left join takes longer query time?
You can use ROW_NUMBER:
;WITH cte AS
(
SELECT a.colId,
rn = ROWN_NUMBER() OVER (PARTITION BY a.col2 ORDER BY a.col1)
FROM table1 a
LEFT JOIN table2 b on a.col1 = b.id
WHERE a.col2 IN (3,5,7)
)
SELECT *
FROM cte
WHERE rn = 1
This will give you the first row for each col2 value and you can restrict the values you want to 3,5,7.

Use of if exists( ) in select statement

I need to fetch a column from table2, if row exists, if not return it as null.
If i use ,case when it fetches only matched rows between table1 and table2.
If i use left outer join it fetches all the rows from table1 even though
condition table1.code='A'
So i need ,some thing like this.
select table1.id,
if(row exist in table2 for query(table2.relation_type_id=55 and table1.id=table2.related_id)
then
return table2.parent_id
else
null
as parent_id,
table1.description,
from table1,table2 where table1.code='A'
SELECT table1.id, table2.parent_id as parent_id
FROM table1
LEFT OUTER JOIN table2 ON (table1.id = table2.related_id)
WHERE table1.code = 'A';
EDIT based on comment :
SELECT table1.id, sub.parent_id as parent_id
FROM table1
LEFT OUTER JOIN (select parent_id,related_id from table2 where relation_type_id =55) sub ON (table1.id = sub.related_id)
WHERE table1.code = 'A';
Have you tried a sub-query?
select table1.id,
(select table2.parent_id from table2 where table2.relation_type_id=55 and table2.related_id=table1.id) parent_id,
table1.description,
from table1 where table1.code='A'

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