Is there an ANSI SQL alternative to the MYSQL LIMIT keyword?

问题

The LIMIT keyword limits the number of rows returned by a SELECT e.g:

SELECT * FROM People WHERE Age > 18 LIMIT 2;

returns 2 rows.

SELECT * FROM People WHERE Age > 18 LIMIT 10, 2;

returns 2 rows after the first 10.

回答1:

this shows the different ways:

-- DB2
select * from table fetch first 10 rows only 
-- Informix 
select first 10 * from table 
-- Microsoft SQL Server and Access 
select top 10 * from table 
-- MySQL and PostgreSQL 
select * from table limit 10 
-- Oracle 
select * from (select * from table) where rownum <= 10

回答2:

Not in SQL:1999.

There are two possible approaches you can use in later standards, with generally low levels of support in today's DBMSs.

In SQL:2008 you can use the DB/2 syntax:

SELECT * FROM things
ORDER BY smell
FETCH FIRST n ROWS ONLY

This only works for “LIMIT n” and not the extended “LIMIT m, n” offset syntax. In SQL:2003 you can use window functions, which can support the extended syntax but is a super PITA:

SELECT * FROM (
    SELECT *, ROW_NUMBER() OVER (ORDER BY smell) AS rn,
    FROM things
)
WHERE rn<=n -- or rn BETWEEN m+1 AND m+n

You will more usually use the DBMS-specific methods today.

回答3:

see also http://en.wikipedia.org/wiki/Select_(SQL)#FETCH_FIRST_clause

SELECT * FROM T LIMIT 10 OFFSET 20 -- Netezza, MySQL, PostgreSQL (also supports the standard, since version 8.4), SQLite, HSQLDB, H2

SELECT * from T WHERE ROWNUM <= 10 -- Oracle (also supports the standard, since Oracle8i)

SELECT FIRST 10 * from T -- Ingres

SELECT FIRST 10 * FROM T order by a -- Informix

SELECT SKIP 20 FIRST 10 * FROM T order by c, d -- Informix (row numbers are filtered after order by is evaluated. SKIP clause was introduced in a v10.00.xC4 fixpack)

SELECT TOP 10 * FROM T -- MS SQL Server, Sybase ASE, MS Access

SELECT TOP 10 START AT 20 * FROM T -- Sybase SQL Anywhere (also supports the standard, since version 9.0.1)

SELECT FIRST 10 SKIP 20 * FROM T -- Interbase, Firebird

SELECT * FROM T ROWS 20 TO 30 -- Firebird (since version 2.1)

SELECT * FROM T
WHERE ID_T > 10 FETCH FIRST 10 ROWS ONLY -- DB2

SELECT * FROM T
WHERE ID_T > 20 FETCH FIRST 10 ROWS ONLY -- DB2 (new rows are filtered after comparing with key column of table T)

回答4:

I don't believe so. All the databases that I'm aware of use vendor-specific keywords for that functionality.

回答5:

Adding to @jle's answer:

SQLite supports LIMIT (MySQL/PostgreSQL)
InterBase/Firebird support SELECT FIRST and SKIP (like Informix)

Also see Emulate MySQL LIMIT clause in Microsoft SQL Server 2000

回答6:

HSQL/H2 uses LIMIT like MySQL

回答7:

Let me link here a related SO question, with a great answer by Lukas Eder and another good answer by bobince:

How universal is the LIMIT statement in SQL?

edit: A few more good reference links, worth to look at in similar cases:

Wikipedia on limiting results and FETCH FIRST in the SELECT statement ;
"Comparison of Different SQL Implementations" on limiting the result sets ;
The jOOQ user manual page on the LIMIT clause from Lukas Eder's answer.

来源：https://stackoverflow.com/questions/595123/is-there-an-ansi-sql-alternative-to-the-mysql-limit-keyword

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