I'm trying to pull some data from a SQLite DB, where I need to execute very similar queries several times. Specifically, I want to pull the list of distinct values out of 3 different columns. I then want to be able to push the list of distinct values into their own arrays, so I can molest them later.

The brute force way to do it is:

# query to get  Centers
$cent_sth=$dbh->prepare("SELECT DISTINCT Center FROM People");
$cent_sth->execute() or die "Failed to retrieve list of centers from d
+atabase. $DBI::errstr";
print " Centers are:\n";
while (@centers = $cent_sth->fetchrow_array()) {
    print "\t@centers[0]\n" unless (@centers[0]!~/^\d{2} -/);
}

# query to get  Divsions
$div_sth=$dbh->prepare("SELECT DISTINCT Div FROM People");
$div_sth->execute() or die "Failed to retrieve list of centers from da
+tabase. $DBI::errstr";
print " Divisions are:\n";
while (@divs = $div_sth->fetchrow_array()) {
    print "\t@divs[0]\n";
}

# query to get  Departments
$dept_sth=$dbh->prepare("SELECT DISTINCT Dept FROM People");
$dept_sth->execute() or die "Failed to retrieve list of centers from d
+atabase. $DBI::errstr";
print " Departments are:\n";
while (@depts = $dept_sth->fetchrow_array()) {
    print "\t@depts[0]\n";
}

[download]

I think I ought to be able to do the same thing by looping over the same code 3 times. Something like:

my %orgs = ("Center", "cent_sth", "Div", "div_sth", "Dept", "dept_sth"
+)
while (($name, $this_sth)=each (%orgs)){
    $this_sth=$dbh->prepare("SELECT DISTINCT $name FROM People");
    $this_sth->execute() or die "Failed to retrieve list of $name from
+ database. $DBI::errstr";
}

[download]

But I'm pretty sure I'm not naming my statement handlers in a way that will allow me to use them later. What's the smart way to do this?

In reply to Looping over multiple queries by Mad_Mac

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