Contributed by BBQ
on May 01, 2000 at 11:25 UTC
Q&A
> database programming
Description: How does one go about selecting X number of rows on a query (e.g. with MySQL)? The desired effect would be to return results from 0-20, then 20-40, and so on.
Answer: How to display from X to Y records using DBI?
contributed by btrott I'll expand on what chromatic wrote, because the
LIMIT keyword can do even more than just that. :)
In addition to specifying the max number
of records to return, you can specify an offset
of where to start in the records being
returned. The syntax is
[LIMIT [offset,] rows]
So, for example, to view records 10-35,
do this:
select log_id
from log_id
limit 10,25
Pretty neat! Consult the
MySQL SELECT docs
for more details and tips. | Answer: How to display from X to Y records using DBI?
contributed by chromatic You could use the SQL command LIMIT:
SELECT * from presidents WHERE terms > 2 LIMIT 10;
You can also use the DBI method fetchall_arrayref(), which will return a reference to a list of rows. Use an array slice to get at the ones you want:
# prepare and execute statement
my $array_ref = $sth->fetchall_arrayref();
# we want 0 through 20
foreach my $row (@$array_ref[0 .. 20]) {
# do something
}
|
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