ShayShay has asked for the wisdom of the Perl Monks concerning the following question:

I'm having a bit of a problem with a project that I'm hoping you all can help me out with. I've looked over some of the documentation and done google searches, but I still can't get it to work.

I'm using SQLite to try to insert a row into a table. I've got variables $gi, $orgName, and $nc that I want to use in my insert statement. I've tried several various ways of writing the statement, including using ? as values and undef afterwards, as well as playing with the " marks. Nothing seems to work.

I'm getting the error:

DBD::SQLite::db prepare failed: near "NC": syntax error(1) at dbdimp.c line 271 at C:\Perl\bin\getAllFiles.pl line 31, <FILE> line 3328.
Can't call method "execute" on an undefined value at C:\Perl\bin\getAllFiles.pl line 40, <FILE> line 3328.

Here's a condensed version of the code from "getAllFiles.pl":

use Cwd;
use Net::FTP;
use DBI;
use strict;

sub dbConnect{
    my ($database, $username, $password, $hostname) = @_;
    my $db = DBI->connect("DBI:SQLite:$database:$hostname", $username,
+ $password) || die "Cannot connect to host database.".$DBI::errstr;
    return $db;
}

sub dbDisconnect{
    my ($db) = @_;
     $db->disconnect;
}

sub dbQuery{
    my ($query) = @_;
        print $query;
    my($database) = "myDB";
    my($username) = "username";
    my($password) = "password";
    my($hostname) = "myHost.com";
    my $db = dbConnect($database, $username, $password, $hostname);
    $query = $db->prepare($query); #LINE 31
    $query->execute; #LINE 40
    $query->finish;
    dbDisconnect($db);
}

my $gi = "11111111";
my $orgName = "some bacteria";
my $nc = "NC_000000";
my $query = "INSERT INTO ORGANISM (ORG_NAME, GI, NC) VALUES ('$gi', '$
+orgName', '$nc')";
            dbQuery($query);

[download]

Replies are listed 'Best First'.
Re: Query Formatting
by ikegami (Patriarch) on Dec 05, 2007 at 22:48 UTC
    Another error is that you don't convert your parameters from text to SQL. That could be done through $db->quote or through replaceable parameters. 
    sub dbQuery{
    my $query = shift @_;
    my($database) = "myDB";
    my($username) = "username";
    my($password) = "password";
    my($hostname) = "myHost.com";
    my $db = dbConnect($database, $username, $password, $hostname);
    $query = $db->prepare($query);
    $query->execute(@_);
    $query->finish;
    dbDisconnect($db);
}

my $gi = "11111111"
my $orgName = "some bacteria"
my $nc = "NC_000000"
my $query = "INSERT INTO ORGANISM ORG_NAME, GI, NC VALUES (?, ?, ?)";
dbQuery($query, $gi, $orgName, $nc);

    [download]

    That will fix a problem unrelated to the one you're asking about.

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Re: Query Formatting
by eserte (Deacon) on Dec 05, 2007 at 22:40 UTC
    It should be VALUES, not VAUES.
[reply]
      Yeah... typo... but it still doesn't work after fixing those...
[reply]
Re: Query Formatting
by KurtSchwind (Chaplain) on Dec 05, 2007 at 22:55 UTC

    Another issue:

    Your Values('$gi' . . . won't replace $gi with "11111111" because it's enclosed in single ticks.

    Update ikegami rightly pointed out that the outside string was double quoted.

    --
    I used to drive a Heisenbergmobile, but every time I looked at the speedometer, I got lost.
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[d/l]
      No, it's in a double-quoted string literal.
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Re: Query Formatting
by tcf03 (Deacon) on Dec 06, 2007 at 10:01 UTC
    This should do what you are looking to do.

    #!/usr/bin/perl

use strict;
use warnings;
use DBI;

sub dbConnect{
    my ($database, $username, $password, $hostname) = @_;
    my $db = DBI->connect("DBI:SQLite:$database:$hostname", $username,
    $password) || die "Cannot connect to host database.".$DBI::errstr;
    return $db;
}

sub dbDisconnect{
    my ($db) = @_;
    $db->disconnect;
}

sub dbINSERT{
    my $table  = shift;
    my $set    = shift;
    my @values = @_;

    my($database) = "myDB";
    my($username) = "username";
    my($password) = "password";
    my($hostname) = "myHost.com";

    my $db = dbConnect($database, $username, $password, $hostname);

    my $vals = join',', map { $db->quote($_) } @values;
    my $query = qq|INSERT into $table ($set) VALUES ($vals)|;
    print "$query\n";

    $query = $db->prepare($query); #LINE 31
    $query->execute; #LINE 40
    $query->finish;
    dbDisconnect($db);
}

sub dbUPDATE{
# Do updates here
}

sub dbDELETE{
# Do deletes here
}

dbINSERT('ORGANISM', 'ORG_NAME, GI, NC', "11111111", "some bacteria", 
+"NC_000000");

    [download]
    Though, I would move the db connection out of the insert/delete/update subs and just do something like this 
    #!/usr/bin/perl

use strict;
use warnings;
use DBI;

sub dbConnect{
    my ($database, $username, $password, $hostname) = @_;
    my $db = DBI->connect("DBI:SQLite:$database:$hostname", $username,
    $password) || die "Cannot connect to host database.".$DBI::errstr;
    return $db;
}

sub dbINSERT{
    my $db     = shift;
    my $table  = shift;
    my $set    = shift;
    my @values = @_;

    my $vals = join',', map { $db->quote($_) } @values;
    my $query = qq|INSERT into $table ($set) VALUES ($vals)|;
    print "$query\n";

    $query = $db->prepare($query); #LINE 31
    return ( $query->execute ) : 0 : 1;
    
}

sub dbUPDATE{
# Do updates here
}

sub dbDELETE{
# Do deletes here
}

my $db = dbConnect("myDB", "username", "password", "myHost.com");
my $status = ( dbINSERT($db, 'ORGANISM', 'ORG_NAME, GI, NC', "11111111
+", "some bacteria", "NC_000000") == 0 ) ? 0 : 1;

END { $db->disconnect }

    [download]
    Its untested, but should work fine for you.

    Update added return code from insert and removed disconnect sub. After re-reading your original post - you may wish to re-add the disconnect sub ( and remove the END block ) as this looks to be part of a larger program

    Ted
    --
    "That which we persist in doing becomes easier, not that the task itself has become easier, but that our ability to perform it has improved."
      --Ralph Waldo Emerson
[reply]
[d/l]
[select]
      one more addition you may want to consider is setting $db->{RaiseError} or $db->{PrintError} or both. 
      sub dbConnect{
    my ($database, $username, $password, $hostname) = @_;
    my $db = DBI->connect("DBI:SQLite:$database:$hostname", $username,
    $password) || die "Cannot connect to host database.".$DBI::errstr;
    $db->{RaiseError} = 1;
    $db->{PrintError} = 1;
    return $db;
}

      [download]
      Ted
      --
      "That which we persist in doing becomes easier, not that the task itself has become easier, but that our ability to perform it has improved."
        --Ralph Waldo Emerson
[reply]
[d/l]

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