Hi all,

Given a query that returns 10,000 rows

if I just want the first 100 Am I better calling fetchrow_hashref 100 times
or
Should I just call fetchall_arrayref get all 10,000 and take the first 100 rows in the array.

my thinking is the query has returned all the data so I am better just to fetch it all rather than repeatedly fetching some of the rows in a loop.

I think fetchall is better as I can use the array size to get the total rowcount instead of doing a second query with a count(*). Assuming I cant rely on $dbh->rows() for selects. so 1 query with fetchall , using array size for the total rows or 2 query multiple limited fetchrow calls and using count for total rows

I guess I am asking is it in theory worth just trying to fetch only what you need if it means you have to do a second query to find the total rows.

cheers

In reply to fetch row or fetchall by hakkr

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