Any way, .. thanks…. for your try..

I need to get TextDescription from Master table for the corresponding ID in transaction table.
Thats all the concept.. if the corresponding ID is not available in Master table.,, we have to omit that record While fetching from Trasaction table.

Thats it………..

EmpNo Description
————————–
1 Mixing
2 Simplex

If it is so, then you can try out the query this way:

SELECT a.EmpNo , b.Description FROM #temp1 a
INNER JOIN #temp2 b ON a.EmpNo = b.BadgeID

Regards,
Raghav

Create table #temp2(BadgeID int Identity Not NUll, Description varchar(20) Not NUll)
Insert into #temp2 values ( ‘Mixing’)
Insert into #temp2 values ( ‘Simplex’)
Insert into #temp2 values ( ‘Combing’)
Insert into #temp2 values ( ‘Adidas’)

Delete from #temp2 where Description = ‘Combing’

——————————————–

Select * from #temp1

Result:
EmpNo BadgeID
1 1
2 NULL
3 3
———————————————

Select * from #temp2

Result :
BadgeID Description
1 Mixing
2 Simplex
4 Adidas
——————————————–

Select a.EmpNo , b.Description from #temp1 a
left outer join
#temp2 b on a.BadgeID = b.BadgeID

Result:
EmpNo Description
1 Mixing
2 NULL
3 NULL

From the above Result, i want to eliminate the last record EmpNo = 3, since its Corresponding BadgeID 3 is not in table #temp2.

I want the result as :

EmpNo Description
1 Mixing
2 NULL

update t1
set t1.col=t2.col
from table1 as t1 inner join table2 as t2 on t1.keycol=t2.keycol
where t2.somecol=

SELECT *
FROM Table1 t1
INNER JOIN Table2 t2 ON t1.ID = t2.ID

Thank you

Regards
janani.S

My Issue is , i want to eliminate records if ID is not available in table t2

Note : t1.Id is Nullable Column in table t1
t2.Id is Not Nullable and Identity Column in table t2

SELECT *
FROM Table1 t1
LEFT JOIN Table2 t2 ON t1.ID = t2.ID WHERE t2.Flag is null

Please Give me Solution for the below Problem!!!!!!!!

SELECT *
FROM Table1 t1
LEFT JOIN Table2 t2 ON t1.ID = t2.ID AND t2.Flag is null

———-

How To Hanle the Query…

If i want want to eliminate Resultant Record when t2.Id is Not Available in Table t2 and t1.Id is Not Null from the above Query Result

Note : t1.Id is Nullable Column in table t1
t2.Id is Not Nullable and Identity Column in table t2

Please Give me Solution for the below Problem!!!!!!!!

SELECT *
FROM Table1 t1
LEFT JOIN Table2 t2 ON t1.ID = t2.ID AND t2.Flag is null

———-

How To Hanle the Query…

If i want want to eliminate Resultant Record when t2.Id is Not Available in Table t2 and t1.Id is Not Null from the above Query Result

———-

How To Hanle Left Join …
If i want want to eliminate Resultant Record when t2.Id is Not Available in Table t2 from the above Query Result

But we do all make mistakes with grammar and punctuation at times, especially when there is no spelling or grammar checker. For example, you failed to punctuate the word ‘however’ correctly in your comment and misplaced the period as well. Your sentende should have read:

(Effect can also be an adjective depending on how it is used; however, affect is always a verb os it is doing something to something else.)

So it goes. I think the meaning of your comment as well as the meaning of Pinal Dave’s title are completely clear. So I would call your comment and mine both nitpicks.

:>)

I am very very glad to have your email and comment. I value and appreciate it 100%. Only friends give feedback.

I realise that English is not your main language and totally admire your ability to master it and write such fantastic articles using it. I hope that you are not offended to be informed of this slight error in what is a very misunderstood area of the language.

“SQL SERVER – Interesting Observation of ON Clause on LEFT JOIN – How ON Clause Effects Resultset in LEFT JOIN”

Should be

“SQL SERVER – Interesting Observation of ON Clause on LEFT JOIN – How ON Clause affects Resultset in LEFT JOIN”

The difference being the word Affects (Effects).
Affect is a verb where one thing affects another.
Effect is a noun where we see the effect that one thing had on the other.
(Effect can also be an adjective depending on how it is used however affect is always a verb os it is doing something to something else).

I think you have done a really good job of explaining the issue. I have often had to explain this weird behaviour to DB developers but in future I think I will simply point them at your example.

Regards

Dave

Your article saved me from committing a big mistake while writing a query.

Thanks for the good work

i have one query
i want to update the data in table 1 based on certain condition which must be satisfy by table 2 how should i do this please give small example
waiting for u r reply

thanks

That being said, my stylistic preference is to put filters in the WHERE clause. Then when I see filters in a JOIN clause, I expect to see an outer join and a reason for the filter being there instead of its normal location.

point 1 )

SELECT *
FROM Table1 t1
LEFT JOIN Table2 t2 ON t1.ID = t2.ID AND t2.Flag = 1

you saying that in above select statement , rows from table2 will be filtered where flag = 1 (i.e. 1 , 2 . 8 will be there ) before joining. Now left join of table1 and table2( rows: 1,2,8) will be there and will get the required result.

Right ?

point 2 )
what if

SELECT *
FROM Table1 t1
LEFT JOIN Table2 t2 ON t1.ID = t2.ID AND t1.Flag = 1

i could not get correct result based on previous assumption.
please explain

SELECT *
FROM Table1 t1
LEFT JOIN Table2 t2 ON t1.ID = t2.ID
AND (t1.flag = 2 and t2.Flag = 1)

In an outer join, the join filters (expressions) that you specify in the ON clause determine which rows of the subordinate table join to the dominant (or outer) table. The dominant table, by definition, returns all its rows in the joined table. That is, a join filter in the ON clause has no effect on the dominant table.

If the ON clause specifies a join filter on the dominant table, the database server joins only those dominant table rows that meet the criterion of the join filter to rows in the subordinate table. The joined result contains all rows from the dominant table.

SELECT *
FROM Table1 t1
LEFT JOIN Table2 t2 ON t1.ID = t2.ID
AND (t1.flag = 1 and t2.Flag = 1)

As per your explaination , it should bring only

1,2,4,6

The results that you get by the query
SELECT *
FROM Table1 t1
LEFT JOIN Table2 t2 ON t1.ID = t2.ID AND t2.Flag is null

Are correct and as expected.

NOTE :
1. Both conditions are in the ON clause so result will be created based on both.
2. Since no WHERE clause all records of Left table will be part of result set.

Step 1:
t1.ID = t2.ID

Results :
1 First 1 1 First 1
2 Second 1 2 Second 1
3 Third 2 3 Third 2
4 Fourth 1 NULL NULL NULL
5 Fifth 2 NULL NULL NULL
6 Sixth 1 NULL NULL NULL
7 Seventh 2 NULL NULL NULL

Step 2 :
AND t2.Flag is null
as per this condition no rows of Table2 from step 1 qualifies hence you see all values as NULL for Table2.
Hope this helps.

–Nilesh

I saw your blog it’s really very nice.
nd this article is very nice and it contain clear explanation.