I would like to know if I could using select statement retrieve exact position of the rows. e.g rows between 235 & 250. Is this possible?
Thanks in advance,
shashi
I don't know of a general way.. but each DB has a way. For example in oracle you can do it with a nested select
Oracle:
select * from (
select a, b, c from table_foo
where id = 124
)
WHERE rownum >= 235
and ROWNUM <= 250
MSSQL
select * from
(select Row_Number() over
(order by userID) as RowIndex, * from users) as Sub
Where Sub.RowIndex >= 235 and Sub.RowIndex <= 250
MySQL
SELECT * FROM TableName LIMIT 235, 15
We can do this by multiple way.
we can do with the help of offset-fetch clause.
select * from Table_Name order by Column_Name offset 234 rows fetch next 16 rows only
it will fetch the record between 235-250. because it will skip first 234 rows and will fetch next 16 rows.
we can use simple select statement with where clause.
Select * from Table_Name where Column_Name Between 235 and 250
it will also fetch same result.
Hope it will help.
If your using mySQL you could use the limit command for example:
SELECT * FROM TableName LIMIT 235, 15
Where the first number is the start index and the second is the number of rows to return.
No, that database is set not a sequence, this mean that You the don't have any specific order.
But when specify the order than everything is much simpler.
Oracle
SELECT * FROM ( SELECT * FROM TABLE ORDER BY COLUMN ) WHERE rownum BETWEEN 235 and 250
In this case You have to use rownum
rownum is a pseudo column. It numbers
the records in a result set. The first
record that meets the where criteria
in a select statement is given
rownum=1, and every subsequent record
meeting that same criteria increases
rownum.
MS SQL
WITH OrderedRecords AS
(
SELECT ColumnA,
ROW_NUMBER() OVER (ORDER BY ColumnA) AS 'RowNumber'
FROM Sales.SalesOrderHeader
)
SELECT * FROM OrderedRecords WHERE RowNumber BETWEEN 235 and 250
GO
For this You have to specify You own order column
For MySQL i don't know how the engine deal with this.
This can be done very easily in SQL Server 2012. By using the new feature of OFFSET and FETCH. This will help you to pull out desired rows in an already ordered/sorted result set.
Please see the below example:
SELECT
PP.FirstName + ' ' + PP.LastName AS 'Name'
,PA.City
,PA.PostalCode
FROM Person.Address PA
INNER JOIN
Person.BusinessEntityAddress PBEA
ON PA.AddressID = PBEA.AddressID
INNER JOIN
Person.Person PP
ON PBEA.BusinessEntityID = PP.BusinessEntityID
ORDER BY PP.FirstName
OFFSET 0 ROWS
FETCH NEXT 5 ROWS ONLY
Please notice the OFFSET 0 and FETCH NEXT 5 written above.
This is will display only 5 rows starting from 0 the row.
In SQL Server,
select * from tablename order by columnname offset 20 rows fetch next 40 rows only
It treats 21st row as 1st row and fetches next 40 rows from a 21st row.
If you're using Microsoft SQL (2005>) you can use the ROW_NUMBER function
USE AdventureWorks;
GO
WITH OrderedOrders AS
(
SELECT SalesOrderID, OrderDate,
ROW_NUMBER() OVER (ORDER BY OrderDate) AS 'RowNumber'
FROM Sales.SalesOrderHeader
)
SELECT *
FROM OrderedOrders
WHERE RowNumber BETWEEN 50 AND 60;
Following worked from me in oracle
select * from (select rownum serial,sp.* from sample_table st) sam
where sam.serial > 10 and sam.serial <= 20;
Related
I am writing a very simple query for an Oracle DB (version 9).
Somehow I can get first 5 rows:
select * from cities where rownum <= 5
But skipping 5 rows returns an empty result:
select * from cities where rownum >= 5
Using:
Oracle SQL Developer
Oracle DB version 9
Why is the second query returning an empty result?
In Oracle Database 12c (release 1) and above, you can do this very simple, for skip 5 rows:
SELECT * FROM T OFFSET 5 ROWS
and for skip 5 rows and take 15 rows:
SELECT * FROM T OFFSET 5 ROWS FETCH NEXT 15 ROWS ONLY
You can use the following query to skip the first not n of rows.
select * from (
select rslts.*, rownum as rec_no from (
<<Query with proper order by (If you don't have proper order by you will see weird results)>>
) rslts
) where rec_no > <<startRowNum - n>>
The above query is similar to pagination query below.
select * from (
select rslts.*, rownum as rec_no from (
<<Query with proper order by (If you don't have proper order by you will see weird results)>>
) rslts where rownum <= <<endRowNum>>
) where rec_no > <<startRowNum>>
Your cities query:
select * from (
select rslts.*, rownum as rec_no from (
select * from cities order by 1
) rslts
) where rec_no > 5 <<startRowNum>>
Note: Assume first column in cities table is unique key
Oracle increments rownum each time it adds a row to the result set. So saying rownum < 5 is fine; as it adds each of the first 5 rows it increments rownum, but then once ruwnum = 5 the WHERE clause stops matching, no more rows are added to the result, and though you don't notice this rownum stops incrementing.
But if you say WHERE rownum > 5 then right off the bat, the WHERE clause doesn't match; and since, say, the first row isn't added to the result set, rownum isn't incremented... so rownum can never reach a value greater than 5 and the WHERE clause can never match.
To get the result you want, you can use row_number() over() in a subquery, like
select *
from (select row_number() over() rn, -- other values
from table
where -- ...)
where rn > 5
Update - As noted by others, this kind of query only makes sense if you can
control the order of the row numbering, so you should really use row_number() over(order bysomething) where something is a useful ordering key in deciding which records are "the first 5 records".
rownum is being increased only when a row is being output, so this type of condition won't work.
In any case, you are not ordering your rows, so what's the point?
Used row_number() over (order by id):
select * from
(select row_number() over (order by id) rn, c.* from countries c)
where rn > 5
Used ROWNUM:
select * from
(select rownum rn, c.* from countries c)
where rn > 5
Important note:
Using alias as countries c instead of countries is required! Without, it gives an error "missing expression"
Even better would be:
select * from mytab sample(5) fetch next 1 rows only;
Sample clause indicates the probability of each row getting picked up in the sampling process. FETCH NEXT clause indicates the number of rows you want to select.
With this code, you can query your table with skip and take.
select * from (
select a.*, rownum rnum from (
select * from cities
) a
) WHERE rnum >= :skip + 1 AND rnum <= :skip + :take
This code works with Oracle 11g. With Oracle 12, there is already a better way to perform this queries with offset and fetch
Suppose I have 500 records in tbl_students. I would like to select records starting from 50 and 250. I know I can use the following way in MySql.
SELECT *
FROM tbl_students
LIMIT 50,100;
I would like to know how to do this in SQL Server. After browsing I have found solution like this.
select top 100 *
from tablename
WHERE column_name BETWEEN 50 AND 250
The issue I am facing is I do not know the values of any column in the table, so I can't write the query like the above. In MySql we can just put the limit for the range without knowing the values inside the column.
Thanks in advance
If you're using SQL Server 2005/08, then you could use a CTE...
;WITH cteRange as
(
select *, rownumber=ROW_NUMBER() OVER (Order by field)
from tablename
)
SELECT * FROM cteRange WHERE rownumber BETWEEN 50 AND 250
if you have SQL Server 2012, then...
SELECT
*
FROM tablename
ORDER BY field
OFFSET 50 ROWS
FETCH NEXT 200 ROWS ONLY
It would be useful to know RDBMS and also what columns you want to extract and Order by, instead of using SELECT *...
It's not clear by what column(s) you want to sort. A table has no implicit order, so you cannot say "give me records between x and y" if you don't specify how you want to order the records.
However, assuming that column_name is the column that you want to use and you're using SQL Server 2005 or newer, you can use a CTE with ROW_NUMBER window function:
WITH CTE AS
(
SELECT t.*, R = ROW_NUMBER() OVER (ORDER BY column_name)
FROM dbo.TableName t
)
SELECT * FROM CTE WHERE RN BETWEEN 50 AND 250
SELECT * FROM (
SELECT *, ROW_NUMBER() OVER (ORDER BY column_name ) as tbl_row FROM tbl_students
) tbl WHERE tbl_row >= 50 and tbl_row <= 250
I think this is one of way available for doing this in SQL Server above version 2005.
I have an SQL Query that i'm running but I only want to select a specific row. For example lets say my query was:
Select * from Comments
Lets say this returns 10 rows, I only want to select the 8th record returned by this query. I know I can do:
Select Top 5 * from Comments
To get the top 5 records of that query but I only want to select a certain record, is there anything I can put into this query to do that (similar to top).
Thanks
jack
This is a classic interview question.
In Ms SQL 2005+ you can use the ROW_NUMBER() keyword and have the Predicate ROW_NUMBER = n
USE AdventureWorks;
GO
WITH OrderedOrders AS
(
SELECT SalesOrderID, OrderDate,
ROW_NUMBER() OVER (ORDER BY OrderDate) AS 'RowNumber'
FROM Sales.SalesOrderHeader
)
SELECT *
FROM OrderedOrders
WHERE RowNumber = 5;
In SQL2000 you could do something like
SELECT Top 1 *FROM
[tblApplications]
where [ApplicationID] In
(
SELECT TOP 5 [ApplicationID]
FROM [dbo].[tblApplications]
order by applicationId Desc
)
How about
SELECT TOP 1 * FROM
(SELECT TOP 8 * FROM Comments ORDER BY foo ASC)
ORDER BY foo DESC
First, you should say which RDBMS you're using.
Second, you should give careful thought to what it is you're trying to accomplish. Relational Databases are set-based. In general, the order of elements in a set does not matter. You'll want to ask why it matters in this case, then see if there's a better way to embed the concept of order into the query itself.
For instance, in SQL Server 2005 (and other RDBMS), you can use the ROW_NUMBER function to assign a sequential number to each row returned, based on the criteria you specify. You could then select rows based on the row number. Example from Books Online:
USE AdventureWorks;
GO
WITH OrderedOrders AS
(
SELECT SalesOrderID, OrderDate,
ROW_NUMBER() OVER (ORDER BY OrderDate) AS 'RowNumber'
FROM Sales.SalesOrderHeader
)
SELECT *
FROM OrderedOrders
WHERE RowNumber BETWEEN 50 AND 60;
SELECT * FROM comments WHERE ...conditions... LIMIT 1 OFFSET 8
OFFSET is a good thing for MySQL
For SQL Server 2005:
select rank() OVER (ORDER BY c.subject, c.date) as rank, c.subject, c.date
from comments c
where rank = 8
Well, in T-SQL (the dialect for SQL Server) you can do the following:
SELECT TOP 1 *
FROM (SELECT TOP 8 *
FROM Table
ORDER
BY SortField)
ORDER
BY SortField DESC
This way you get the 8th record.
I have read the question & your comments on you would want next 3 blog comments etc.
How is your tables structured?
Assume that you have blog post Id & comment Id is generated in ascending order for each blog post, you could do a SELECT based on the current Id.
e.g. if the blogpostId = 101, you get the top 3 comments order by posted Id. Now lets say, you want to get the next 3 comments - you could do a SELECT WHERE commentId between the last comment id shown TO the comment id - 3
But all that depends on how your tables are defined.
In SQL 2000 where you do not have ROW_NUMBER() function you could use a work-around like this:
SELECT CommentsTableFieldList, IDENTITY(INT, 1,1) as seqNo
INTO #SeqComments
FROM Comments
SELECT * FROM #SeqComments
WHERE seqNo = 8
select top 1 *
from TableName
where ColumnName1 in
(
select top nth ColumnName1
from TableName
order by ColumnName1 desc
)
order by ColumnName1 desc
From the SELECT reference, use the LIMIT keyword:
SELECT * FROM tbl LIMIT 5,10; # Retrieve rows 6-15
SELECT * FROM tbl LIMIT 5; # Retrieve first 5 rows
Note: this is for MySQL, other SQL engines may have a different keyword.
Select from tablename limit nthrow,1;
try This
Let us assume , We want select 5th row of WC_Video Table
And
Select * from (Select Row_Number() over (Order by Uploadedon) as 'rownumber',* from Wc_Video )as Temp where rownumber=5
In SQL Server, TOP may be used to return the first n number of rows in a query. For example, SELECT TOP 100 * FROM users ORDER BY id might be used to return the first 100 people that registered for a site. (This is not necessarily the best way, I am just using it as an example).
My question is - What is the equivalent to TOP in other databases, such as Oracle, MySQL, PostgreSQL, etc? If there is not an equivalent keyword, what workarounds can you recommend to achieve the same result?
To select first 100 rows:
MySQL and PostgreSQL:
SELECT *
FROM Table
ORDER BY
column
LIMIT 100
Oracle:
SELECT *
FROM (
SELECT t.*
FROM table
ORDER BY
column
)
WHERE rownum <= 100
Note that you need a subquery here. If you don't add a subquery, ROWNUM will select first 10 rows in random order and then sort them by column.
To select rows between 100 and 300:
MySQL:
SELECT *
FROM TABLE
ORDER BY
column
LIMIT 100, 200
PostgreSQL:
SELECT *
FROM Table
ORDER BY
column
OFFSET 100 LIMIT 200
Oracle:
SELECT *
FROM (
SELECT t.*, ROW_NUMBER() OVER (ORER BY column) AS rn
FROM table
)
WHERE rn >= 100
AND rownum <= 200
Note that an attempt to simplify it with ROWNUM BETWEEN 100 AND 200 (as opposed to rn BETWEEN 100 AND 200 in the outer query) will return nothing in Oracle!
RN BETWEEN 100 AND 200 will work in Oracle too but is less efficient.
See the article in my blog for performance details:
Oracle: ROW_NUMBER vs ROWNUM
For Postgres and MySQL it's the LIMIT keyword.
SELECT *
FROM users
ORDER BY id
LIMIT 100;
This is standard SQL (Oracle and SQL Server implement it). This is an example of returning up to 100 rows:
SELECT ID_CONTROL FROM (SELECT ROW_NUMBER() OVER (ORDER BY ID_CONTROL)
ROWNUMBER, ID_CONTROL FROM IWS_CONTROL WHERE
CURRENT_STATE = 15 AND CURRENT_STATUS=0) A WHERE ROWNUMBER <= 100)
In SQL Anywhere, it's the same as SQL Server:
SELECT TOP 100 * FROM users ORDER BY id
You can even start in the middle of the result set if you want:
SELECT TOP 100 START AT 50 * FROM users ORDER BY id
gets the 50th through 150th rows of the result set.
LIMIT 100
as in
SELECT * FROM foo ORDER BY bar LIMIT 100
You can use RANK() and DENSE_RANK() in Oracle. Here is a link to AskTom website explaining how to to pagination and top-n queries with DENSE_RANK in Oracle.
Oracle:
select * from (select * from foo ORDER BY bar) where rownum < 100
With a nice explanation on how to make it work in AskTom.
In Ingres the same query would by:
select First 100 * from foo ORDER BY bar
Ingres question was already answered in StackOverflow before.
In DB2 you would make your query look like this:
SELECT * FROM tblData FETCH FIRST 10 ROWS ONLY;
In Oracle you want to use a TOP-N query.
For example:
select *
from (SELECT *
FROM foo
where foo_id=[number]
order by foo_id desc)
where rownum <= 3
This will get you the top three results (because I order by desc in the sub query)
This question already has answers here:
Implement paging (skip / take) functionality with this query
(6 answers)
Closed 1 year ago.
I have this query with MySQL:
select * from table1 LIMIT 10,20
How can I do this with SQL Server?
Starting SQL SERVER 2005, you can do this...
USE AdventureWorks;
GO
WITH OrderedOrders AS
(
SELECT SalesOrderID, OrderDate,
ROW_NUMBER() OVER (ORDER BY OrderDate) AS 'RowNumber'
FROM Sales.SalesOrderHeader
)
SELECT *
FROM OrderedOrders
WHERE RowNumber BETWEEN 10 AND 20;
or something like this for 2000 and below versions...
SELECT TOP 10 * FROM (SELECT TOP 20 FROM Table ORDER BY Id) ORDER BY Id DESC
Starting with SQL SERVER 2012, you can use the OFFSET FETCH Clause:
USE AdventureWorks;
GO
SELECT SalesOrderID, OrderDate
FROM Sales.SalesOrderHeader
ORDER BY SalesOrderID
OFFSET 10 ROWS
FETCH NEXT 10 ROWS ONLY;
GO
http://msdn.microsoft.com/en-us/library/ms188385(v=sql.110).aspx
This may not work correctly when the order by is not unique.
If the query is modified to ORDER BY OrderDate, the result set returned is not as expected.
This is how I limit the results in MS SQL Server 2012:
SELECT *
FROM table1
ORDER BY columnName
OFFSET 10 ROWS FETCH NEXT 10 ROWS ONLY
NOTE: OFFSET can only be used with or in tandem to ORDER BY.
To explain the code line OFFSET xx ROWS FETCH NEXT yy ROW ONLY
The xx is the record/row number you want to start pulling from in the table, i.e: If there are 40 records in table 1, the code above will start pulling from row 10.
The yy is the number of records/rows you want to pull from the table.
To build on the previous example: If table 1 has 40 records and you began pulling from row 10 and grab the NEXT set of 10 (yy).
That would mean, the code above will pull the records from table 1 starting at row 10 and ending at 20. Thus pulling rows 10 - 20.
Check out the link for more info on OFFSET
This is almost a duplicate of a question I asked in October:
Emulate MySQL LIMIT clause in Microsoft SQL Server 2000
If you're using Microsoft SQL Server 2000, there is no good solution. Most people have to resort to capturing the result of the query in a temporary table with a IDENTITY primary key. Then query against the primary key column using a BETWEEN condition.
If you're using Microsoft SQL Server 2005 or later, you have a ROW_NUMBER() function, so you can get the same result but avoid the temporary table.
SELECT t1.*
FROM (
SELECT ROW_NUMBER OVER(ORDER BY id) AS row, t1.*
FROM ( ...original SQL query... ) t1
) t2
WHERE t2.row BETWEEN #offset+1 AND #offset+#count;
You can also write this as a common table expression as shown in #Leon Tayson's answer.
SELECT *
FROM (
SELECT TOP 20
t.*, ROW_NUMBER() OVER (ORDER BY field1) AS rn
FROM table1 t
ORDER BY
field1
) t
WHERE rn > 10
Syntactically MySQL LIMIT query is something like this:
SELECT * FROM table LIMIT OFFSET, ROW_COUNT
This can be translated into Microsoft SQL Server like
SELECT * FROM
(
SELECT TOP #{OFFSET+ROW_COUNT} *, ROW_NUMBER() OVER (ORDER BY (SELECT 1)) AS rnum
FROM table
) a
WHERE rnum > OFFSET
Now your query select * from table1 LIMIT 10,20 will be like this:
SELECT * FROM
(
SELECT TOP 30 *, ROW_NUMBER() OVER (ORDER BY (SELECT 1)) AS rnum
FROM table1
) a
WHERE rnum > 10
SELECT TOP 10 * FROM table;
Is the same as
SELECT * FROM table LIMIT 0,10;
Here's an article about implementing Limit in MsSQL Its a nice read, specially the comments.
This is one of the reasons I try to avoid using MS Server... but anyway. Sometimes you just don't have an option (yei! and I have to use an outdated version!!).
My suggestion is to create a virtual table:
From:
SELECT * FROM table
To:
CREATE VIEW v_table AS
SELECT ROW_NUMBER() OVER (ORDER BY table_key) AS row,* FROM table
Then just query:
SELECT * FROM v_table WHERE row BETWEEN 10 AND 20
If fields are added, or removed, "row" is updated automatically.
The main problem with this option is that ORDER BY is fixed. So if you want a different order, you would have to create another view.
UPDATE
There is another problem with this approach: if you try to filter your data, it won't work as expected. For example, if you do:
SELECT * FROM v_table WHERE field = 'test' AND row BETWEEN 10 AND 20
WHERE becomes limited to those data which are in the rows between 10 and 20 (instead of searching the whole dataset and limiting the output).
In SQL there's no LIMIT keyword exists. If you only need a limited number of rows you should use a TOP keyword which is similar to a LIMIT.
Must try. In below query, you can see group by, order by, Skip rows, and limit rows.
select emp_no , sum(salary_amount) from emp_salary
Group by emp_no
ORDER BY emp_no
OFFSET 5 ROWS -- Skip first 5
FETCH NEXT 10 ROWS ONLY; -- limit to retrieve next 10 row after skiping rows
Easy way
MYSQL:
SELECT 'filds' FROM 'table' WHERE 'where' LIMIT 'offset','per_page'
MSSQL:
SELECT 'filds' FROM 'table' WHERE 'where' ORDER BY 'any' OFFSET 'offset'
ROWS FETCH NEXT 'per_page' ROWS ONLY
ORDER BY is mandatory
This is a multi step approach that will work in SQL2000.
-- Create a temp table to hold the data
CREATE TABLE #foo(rowID int identity(1, 1), myOtherColumns)
INSERT INTO #foo (myColumns) SELECT myData order By MyCriteria
Select * FROM #foo where rowID > 10
SELECT
*
FROM
(
SELECT
top 20 -- ($a) number of records to show
*
FROM
(
SELECT
top 29 -- ($b) last record position
*
FROM
table -- replace this for table name (i.e. "Customer")
ORDER BY
2 ASC
) AS tbl1
ORDER BY
2 DESC
) AS tbl2
ORDER BY
2 ASC;
-- Examples:
-- Show 5 records from position 5:
-- $a = 5;
-- $b = (5 + 5) - 1
-- $b = 9;
-- Show 10 records from position 4:
-- $a = 10;
-- $b = (10 + 4) - 1
-- $b = 13;
-- To calculate $b:
-- $b = ($a + position) - 1
-- For the present exercise we need to:
-- Show 20 records from position 10:
-- $a = 20;
-- $b = (20 + 10) - 1
-- $b = 29;
If your ID is unique identifier type or your id in table is not sorted you must do like this below.
select * from
(select ROW_NUMBER() OVER (ORDER BY (select 0)) AS RowNumber,* from table1) a
where a.RowNumber between 2 and 5
The code will be
select * from limit 2,5
better use this in MSSQLExpress 2017.
SELECT * FROM
(
SELECT ROW_NUMBER() OVER (ORDER BY (SELECT 0)) as [Count], * FROM table1
) as a
WHERE [Count] BETWEEN 10 and 20;
--Giving a Column [Count] and assigning every row a unique counting without ordering something then re select again where you can provide your limits.. :)
One of the possible way to get result as below , hope this will help.
declare #start int
declare #end int
SET #start = '5000'; -- 0 , 5000 ,
SET #end = '10000'; -- 5001, 10001
SELECT * FROM (
SELECT TABLE_NAME,TABLE_TYPE, ROW_NUMBER() OVER (ORDER BY TABLE_NAME) as row FROM information_schema.tables
) a WHERE a.row > #start and a.row <= #end
If i remember correctly (it's been a while since i dabbed with SQL Server) you may be able to use something like this: (2005 and up)
SELECT
*
,ROW_NUMBER() OVER(ORDER BY SomeFields) AS [RowNum]
FROM SomeTable
WHERE RowNum BETWEEN 10 AND 20