I was called many times by Jr. Programmers in team to debug their SQL. I keep log of most of the problems and review them afterwards. This helps me to evaluate my team and identify most important next thing which I can do to improve the performance and productivity of it. Recently we have many new hires and they had almost similar questions. Since, I have send them following sequence of the SELECT clause I am not interrupted often, which helps me to focus on larger project architectural design.
SELECT yourcolumns
FROM tablenames
JOIN tablenames
WHERE condition
GROUP BY yourcolumns
HAVING aggregatecolumn condition
ORDER BY yourcolumns
Once above order is memorized it guides the basic construction of SELECT statement. This article is written keeping in mind beginners in SQL Server language and presents very higher level outline of SELECT statement.
Reference : Pinal Dave (https://blog.sqlauthority.com)
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Hi Pinal
I hav a question,
Why we use group by clause before order by clause.
Ashutosh
How Can we generate incremented linear number in sql server
as in oracle we genaerate in via sequence …
I want the o/p like–
1
2
3
4
5
6
7
8
9
hi ,Pinal
i didnt understand
how to debugging the stored procedures in sqlserver2005
Please give me answer
thnaks & Regards
Hi, pinal
how to use searchable keyword in asp.net with sql server
Please give me answer
thnaks & Regards
select row_number() over(partition by gender order by empname) as Srno,* from Employees
Row_Number Function have following syntax
Row_Number() Over([Partition by columnName] Order by columnName)
where Partition by is optional but Order by is compulsory.
use This code you can get the serial order
select row_number() over(partition by gender order by empname) as Srno,* from Employees
Row_Number Function have following syntax
Row_Number() Over([Partition by columnName] Order by columnName)
where Partition by is optional but Order by is compulsory.
Row_Number funciton returns sequence for each row based on Order by clause, if you mention partition by also row number will split rows based on partition by column and then generate the separate sequence numbers.
Hi nagender,
please tell me what the means of serial order.
Actually i ran you code using temp table
Find below code and give me suggestion.
Sorry but i am beginner.
create table #emp(empName nvarchar(10),gender nvarchar(10))
select * from #emp
insert into #emp(empName,gender)values(‘xyz’,’male’)
insert into #emp(empName,gender)values(‘mno’,’male’)
insert into #emp(empName,gender)values(‘kld’,’female’)
insert into #emp(empName,gender)values(‘clg’,’female’)
select row_number() over(partition by empName order by gender) as Srno,* from #emp
Output:-
Srno empName gender
1 clg female
1 kld female
1 mno male
1 xyz male
my question is in result not showing sequence no.
Wooow,great solution nagender. thanks alot,a have been looking for this solution for long time ago. Nice job.
Hi pinal,
I have to prepare a SSIS package which takes data from a table say a and then transfers data between two tables say b and c based on information of table a.
is it possible through SSIS?
if it is please tell me how it can be done?
is this in right order:
1. SELECT
2. FROM
3. JOIN
4. ON
5. WHERE
6. GROUP BY
7. HAVING
8. ORDER BY
It is also useful to know the order of evaluation in order to realise why, for example, column aliases are only usable in the ORDER BY clause and not the GROUP BY
(5) SELECT (6) DISTINCT
(1) FROM
(2) WHERE
(3) GROUP BY
(4) HAVING
(7) ORDER BY
I have this data
ID Name State Check
1 Raj UP ok
1 Raj UP Notok
2 bob MP ok
2 bob MP ok
3 joy MH Notok
3 joy MH Notok
I want following data
ID Name State Check flag
1 Raj UP ok y
1 Raj UP Notok n
2 bob MP ok y
2 bob MP ok n
3 joy MH Notok y
3 joy MH Notok n