How to select the nth row in a SQL database table?

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I'm interested in learning some (ideally) database agnostic ways of selecting the nth row from a database table. It would also be interesting to see how this can be achieved using the native functionality of the following databases:

  • SQL Server
  • MySQL
  • PostgreSQL
  • SQLite
  • Oracle

I am currently doing something like the following in SQL Server 2005, but I'd be interested in seeing other's more agnostic approaches:

WITH Ordered AS (
SELECT ROW_NUMBER() OVER (ORDER BY OrderID) AS RowNumber, OrderID, OrderDate
FROM Orders)
SELECT *
FROM Ordered
WHERE RowNumber = 1000000

Credit for the above SQL: Firoz Ansari's Weblog

Update: See Troels Arvin's answer regarding the SQL standard. Troels, have you got any links we can cite?

33 Answers

There are ways of doing this in optional parts of the standard, but a lot of databases support their own way of doing it.

A really good site that talks about this and other things is http://troels.arvin.dk/db/rdbms/#select-limit.

Basically, PostgreSQL and MySQL supports the non-standard:

SELECT...
LIMIT y OFFSET x 

Oracle, DB2 and MSSQL supports the standard windowing functions:

SELECT * FROM (
  SELECT
    ROW_NUMBER() OVER (ORDER BY key ASC) AS rownumber,
    columns
  FROM tablename
) AS foo
WHERE rownumber <= n

(which I just copied from the site linked above since I never use those DBs)

Update: As of PostgreSQL 8.4 the standard windowing functions are supported, so expect the second example to work for PostgreSQL as well.

Update: SQLite added window functions support in version 3.25.0 on 2018-09-15 so both forms also work in SQLite.

PostgreSQL supports windowing functions as defined by the SQL standard, but they're awkward, so most people use (the non-standard) LIMIT / OFFSET:

SELECT
    *
FROM
    mytable
ORDER BY
    somefield
LIMIT 1 OFFSET 20;

This example selects the 21st row. OFFSET 20 is telling Postgres to skip the first 20 records. If you don't specify an ORDER BY clause, there's no guarantee which record you will get back, which is rarely useful.

I'm not sure about any of the rest, but I know SQLite and MySQL don't have any "default" row ordering. In those two dialects, at least, the following snippet grabs the 15th entry from the_table, sorting by the date/time it was added:

SELECT * 
FROM the_table 
ORDER BY added DESC 
LIMIT 1,15

(of course, you'd need to have an added DATETIME field, and set it to the date/time that entry was added...)

SQL 2005 and above has this feature built-in. Use the ROW_NUMBER() function. It is excellent for web-pages with a << Prev and Next >> style browsing:

Syntax:

SELECT
    *
FROM
    (
        SELECT
            ROW_NUMBER () OVER (ORDER BY MyColumnToOrderBy) AS RowNum,
            *
        FROM
            Table_1
    ) sub
WHERE
    RowNum = 23

I suspect this is wildly inefficient but is quite a simple approach, which worked on a small dataset that I tried it on.

select top 1 field
from table
where field in (select top 5 field from table order by field asc)
order by field desc

This would get the 5th item, change the second top number to get a different nth item

SQL server only (I think) but should work on older versions that do not support ROW_NUMBER().

Contrary to what some of the answers claim, the SQL standard is not silent regarding this subject.

Since SQL:2003, you have been able to use "window functions" to skip rows and limit result sets.

And in SQL:2008, a slightly simpler approach had been added, using
OFFSET skip ROWS FETCH FIRST n ROWS ONLY

Personally, I don't think that SQL:2008's addition was really needed, so if I were ISO, I would have kept it out of an already rather large standard.

1 small change: n-1 instead of n.

select *
from thetable
limit n-1, 1

When we used to work in MSSQL 2000, we did what we called the "triple-flip":

EDITED

DECLARE @InnerPageSize int
DECLARE @OuterPageSize int
DECLARE @Count int

SELECT @Count = COUNT(<column>) FROM <TABLE>
SET @InnerPageSize = @PageNum * @PageSize
SET @OuterPageSize = @Count - ((@PageNum - 1) * @PageSize)

IF (@OuterPageSize < 0)
    SET @OuterPageSize = 0
ELSE IF (@OuterPageSize > @PageSize)
    SET @OuterPageSize = @PageSize

DECLARE @sql NVARCHAR(8000)

SET @sql = 'SELECT * FROM
(
    SELECT TOP ' + CAST(@OuterPageSize AS nvarchar(5)) + ' * FROM
    (
        SELECT TOP ' + CAST(@InnerPageSize AS nvarchar(5)) + ' * FROM <TABLE> ORDER BY <column> ASC
    ) AS t1 ORDER BY <column> DESC
) AS t2 ORDER BY <column> ASC'

PRINT @sql
EXECUTE sp_executesql @sql

It wasn't elegant, and it wasn't fast, but it worked.

In Oracle 12c, You may use OFFSET..FETCH..ROWS option with ORDER BY

For example, to get the 3rd record from top:

SELECT * 
FROM   sometable
ORDER BY column_name
OFFSET 2 ROWS FETCH NEXT 1 ROWS ONLY;

ADD:

LIMIT n,1

That will limit the results to one result starting at result n.

Oracle:

select * from (select foo from bar order by foo) where ROWNUM = x

For SQL Server, a generic way to go by row number is as such:

SET ROWCOUNT @row --@row = the row number you wish to work on.

For Example:

set rowcount 20   --sets row to 20th row

select meat, cheese from dbo.sandwich --select columns from table at 20th row

set rowcount 0   --sets rowcount back to all rows

This will return the 20th row's information. Be sure to put in the rowcount 0 afterward.

Here's a generic version of a sproc I recently wrote for Oracle that allows for dynamic paging/sorting - HTH

-- p_LowerBound = first row # in the returned set; if second page of 10 rows,
--                this would be 11 (-1 for unbounded/not set)
-- p_UpperBound = last row # in the returned set; if second page of 10 rows,
--                this would be 20 (-1 for unbounded/not set)

OPEN o_Cursor FOR
SELECT * FROM (
SELECT
    Column1,
    Column2
    rownum AS rn
FROM
(
    SELECT
        tbl.Column1,
        tbl.column2
    FROM MyTable tbl
    WHERE
        tbl.Column1 = p_PKParam OR
        tbl.Column1 = -1
    ORDER BY
        DECODE(p_sortOrder, 'A', DECODE(p_sortColumn, 1, Column1, 'X'),'X'),
        DECODE(p_sortOrder, 'D', DECODE(p_sortColumn, 1, Column1, 'X'),'X') DESC,
        DECODE(p_sortOrder, 'A', DECODE(p_sortColumn, 2, Column2, sysdate),sysdate),
        DECODE(p_sortOrder, 'D', DECODE(p_sortColumn, 2, Column2, sysdate),sysdate) DESC
))
WHERE
    (rn >= p_lowerBound OR p_lowerBound = -1) AND
    (rn <= p_upperBound OR p_upperBound = -1);

But really, isn't all this really just parlor tricks for good database design in the first place? The few times I needed functionality like this it was for a simple one off query to make a quick report. For any real work, using tricks like these is inviting trouble. If selecting a particular row is needed then just have a column with a sequential value and be done with it.

For SQL server, the following will return the first row from giving table.

declare @rowNumber int = 1;
    select TOP(@rowNumber) * from [dbo].[someTable];
EXCEPT
    select TOP(@rowNumber - 1) * from [dbo].[someTable];

You can loop through the values with something like this:

WHILE @constVar > 0
BEGIN
    declare @rowNumber int = @consVar;
       select TOP(@rowNumber) * from [dbo].[someTable];
    EXCEPT
       select TOP(@rowNumber - 1) * from [dbo].[someTable];  

       SET @constVar = @constVar - 1;    
END;

LIMIT n,1 doesn't work in MS SQL Server. I think it's just about the only major database that doesn't support that syntax. To be fair, it isn't part of the SQL standard, although it is so widely supported that it should be. In everything except SQL server LIMIT works great. For SQL server, I haven't been able to find an elegant solution.

In Sybase SQL Anywhere:

SELECT TOP 1 START AT n * from table ORDER BY whatever

Don't forget the ORDER BY or it's meaningless.

I'm a bit late to the party here but I have done this without the need for windowing or using

WHERE x IN (...)
SELECT TOP 1
--select the value needed from t1
[col2]
FROM
(
   SELECT TOP 2 --the Nth row, alter this to taste
   UE2.[col1],
   UE2.[col2],
   UE2.[date],
   UE2.[time],
   UE2.[UID]
   FROM
   [table1] AS UE2
   WHERE
   UE2.[col1] = ID --this is a subquery 
   AND
   UE2.[col2] IS NOT NULL
   ORDER BY
   UE2.[date] DESC, UE2.[time] DESC --sorting by date and time newest first
) AS t1
ORDER BY t1.[date] ASC, t1.[time] ASC --this reverses the order of the sort in t1

It seems to work fairly fast although to be fair I only have around 500 rows of data

This works in MSSQL

unbelievable that you can find a SQL engine executing this one ...

WITH sentence AS
(SELECT 
    stuff,
    row = ROW_NUMBER() OVER (ORDER BY Id)
FROM 
    SentenceType
    )
SELECT
    sen.stuff
FROM sentence sen
WHERE sen.row = (ABS(CHECKSUM(NEWID())) % 100) + 1
SELECT * FROM emp a
WHERE  n = ( 
    SELECT COUNT( _rowid)
    FROM emp b
    WHERE a. _rowid >= b. _rowid
);

Most suitable answer I have seen on this article for sql server

WITH myTableWithRows AS (
    SELECT (ROW_NUMBER() OVER (ORDER BY myTable.SomeField)) as row,*
    FROM myTable)
SELECT * FROM myTableWithRows WHERE row = 3

If you want to look at native functionalities: MySQL, PostgreSQL, SQLite, and Oracle (basically SQL Server doesn't seem to have this function) you could ACTUALLY use the NTH_VALUE window function. Oracle Source: Oracle Functions: NTH_VALUE

I've actually experimented with this in our Oracle DB to do some comparing of the first row (after ordering) to the second row (again, after ordering). The code would look similar to this (in case you don't want to go to the link):

SELECT DISTINCT dept_id
     , NTH_VALUE(salary,2) OVER (PARTITION BY dept_id ORDER BY salary DESC
           RANGE BETWEEN UNBOUNDED PRECEDING AND UNBOUNDED FOLLOWING) 
        AS "SECOND HIGHEST"
     , NTH_VALUE(salary,3) OVER (PARTITION BY dept_id ORDER BY salary DESC
           RANGE BETWEEN UNBOUNDED PRECEDING AND UNBOUNDED FOLLOWING)
        AS "THIRD HIGHEST"
  FROM employees
 WHERE dept_id in (10,20)
 ORDER 
    BY dept_id;

I've found it quite interesting and I wish they'd let me use it.

WITH r AS (
  SELECT TOP 1000 * FROM emp
)
SELECT * FROM r
EXCEPT
SELECT TOP 999 FROM r

This will give the 1000th row in SQL Server.

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