Hi Monks,

I tried to retrieve only one column from db every time and combine each time result into an array.

I know I can use "selectcol_arrayref" to do this job, and it works.

However, I kind of doubt its performance. I tried to use a statement handle with a place holder to do it. so I can prepare a query first, and each loop of execute will return all the rows of one single column.

Just didn't find such info anywhere.

could someone give me some hints? thank you. 
foreach $id (@id){
 $statement = qq{select val1 from tb11 where x=$id};
 $col_ref = $dbh->selectcol_arrayref($statement);
 push @ary,$col_ref;
}

[download]

above is what I did, which actually just return the values of one column.

now, I want to put the query statement out of the loop,

and use something like $sth->prepare(qq{select val1 from tbl1 where x= ?}),

then in the loop try to do $sth->execute($id) to get the value.

But I want to get the whole column values at once, not just reference to array of reference.

I am wondering if there is a function for statement handle to return all the values for a single column by just one call.

In reply to How to use Perl DBI to select just on column of db by lightoverhead

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