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5.2. Does Derby support a LIMIT command?


Derby supports limiting the number of rows returned by a query through JDBC. For example, to fetch the first 5 rows of a large table:

Statement stmt = con.createStatement();
stmt.setMaxRows(5);
ResultSet rs = stmt.executeQuery("SELECT * FROM myLargeTable");

Some related tuning tips are available in this external article.

Starting with the 10.4.1.3 release Derby also supports limiting the number of rows using the ROW_NUMBER function.

For example, to fetch the first 5 rows of a large table:

SELECT * FROM ( 
    SELECT ROW_NUMBER() OVER() AS rownum, myLargeTable.* 
    FROM myLargeTable 
) AS tmp 
WHERE rownum <= 5; 

 

The ROW_NUMBER function can also be used to select a limited number of rows starting with an offset, for example:

SELECT * FROM ( 
    SELECT ROW_NUMBER() OVER() AS rownum, myLargeTable.* 
    FROM myLargeTable 
) AS tmp 
WHERE rownum > 200000 AND rownum <= 200005; 

 

For more information, refer to the ROW_NUMBER built-in function in the Derby Reference Manual (available from the Documentation page). Development notes are available on the OLAPRowNumber wiki page.

The LIMIT keyword is not defined in the SQL standard, and is currently not supported.