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selectcol_arrayref not working/available?

( #103522=categorized question: print w/ replies, xml ) Need Help??
Contributed by christopherbarsuk on Aug 09, 2001 at 21:34 UTC
Q&A  > database programming


Description:

I'm using DBI with a MySQL database, and, reading through the documentation, I see the method 'selectcol_arrayref' -- when I try this method, it always returns 'undef'.

Q1: Is this method actually available?

Q2: Is there a way to determine what module is supplying an inherited method? That is, if I want to look at the code for this method, how do I determine where from it's being inherited?

Muchas thanks for any insight...

Answer: selectcol_arrayref not working/available?
contributed by tadman

I use selectcol_arrayref all the time, and it works very well. Make sure you are checking the value of your $dbh->err, and $dbh->errstr because there may be an error in your query.

The difference between selectcol_arrayref and selectall_arrayref is that the former returns a single array of all values in that column, while the latter returns an array of arrays of each row (AoA), even if each row contains only one entry. This is why the former is preferable for these kinds of circumstances.

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