Pagination query(SQL) in AS400/DB2

问题

I have been working on try to create php web-based paging for our tables which have over a million rows.

Based on what I have read, I have 3 options

retrieve all rows in resultset - not possiblefor me coz of the size
retrieve 1000 rows, store in temp table and create an iterator for it and page through it - too many queries - too many inserts!!
run a query each time if someone opts page forward or backwards

Right now I am trying to get option 3 working. I have the first page showing up as "select * from accout order by acct fetch first 10 rows only" Page next "select * from account where acct>(last record) order by acct fetch first 10 only" page last record "select * from account where acct=(select max(acct) from account)"

The problem is showing the previous page and i really would appreciate help in this.

回答1:

SELECT *
  FROM (
    SELECT 
      *, 
      ROW_NUMBER() OVER (ORDER BY acct) AS RowNum
    FROM 
      account
  ) AS Data
WHERE 
  RowNum BETWEEN 100 AND 110;

First, you should get rid of the SELECT *. Select only the fields you need.

Place an index on acct, this will help the ROW_NUMBER() OVER (ORDER BY acct) construct.

Use a SELECT COUNT(*) FROM account to determine how many pages you will have.

Also read Fastest most/efficient way to do pagination with SQL searching DB2

回答2:

The LIMIT..OFFSET solution is supported in DB2 10+.. For older versions, you have to enable the MySQL compatibility with:

$ db2set DB2_COMPATIBILITY_VECTOR=MYS
$ db2stop
$ db2start

in db2cmd in order to use that syntax.

回答3:

SELECT * FROM foo LIMIT 10, 1;

try the limit and offset in mysql..

this mostly use in creating pagination

来源：https://stackoverflow.com/questions/14036838/pagination-querysql-in-as400-db2

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