Quickly generate CSV or TSV from SQL query

Sometimes to produce CSV or TSV from information in a MySQL database, all you have to do is:

echo 'some SELECT query ...' | mysql mydb >data.tsv

but for more complex things, you'll often need to use scripting like with Perl to do some munging first. When you're ready to output the data with:


the data is in a Perl data structure. How to quickly output CSV? I've looked at DBI::Format and DBIx::CSVDumper and they are cumbersome especially if you want something brief for one-liners: you need to instantiate a separate object with some parameters, then call an additional one or more methods. You might as well just do this with the standard Text::CSV (or Text::CSV_XS):

use Text::CSV;
my $csv = Text::CSV->new;

$csv->print(\*STDOUT, $sth->{NAME});
while (my $row = $sth->fetchrow_arrayref) {
     $csv->print(\*STDOUT, $row);

For TSV it's even shorter (note: fail spectacularly when data contains Tab character, but that is relatively rare):

say join("\t", @{$sth->{NAME}});
while (my $row = $sth->fetchrow_arrayref) {
     say join("\t", @$row);

My modules DBIx::CSV and DBIx::TSV attempt to offer something even briefer (for CSV, at least). Instead of fetchrow_arrayref or fetchall_arrayref (or selectrow_arrayref, selectall_arrayref), you use fetchrow_csv and friends:

print $sth->fetchall_csv;

This automatically prints the header too, and if you don't want header:

print $sth->fetchall_csv_noheader;

For even more text table formats, like ASCII table, Org table, Markdown table, and so on, I've also written DBIx::TextTableAny.

I've also just written DBIx::Conn::MySQL after being tired from writing the gazillionth one-liner to connect to MySQL database. Now, instead of:

% perl -MDBI -E'my $dbh = DBI->connect("dbi:mysql:database=mydb", "username", "password"); $sth = $dbh->prepare(...)'

you can now write this:

% perl -MDBI::Conn::MySQL=mydb -E'$sth = $dbh->prepare(...)'

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