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error in execution.

Posted by revtopo (revtopo), 27 September 2007
I have written a code to get a list of projects with id =72 using perl scripts. I have connected that with mysql database using DBI.

my code goes goes this way:

use DBI;
use strict;
my $connect;
my $database = 'Cloned_RNA_2_dev';
my $user ='root';
my $pass = '';
my $host = 'localhost';
my $dsn = qq(DBI:mysql:database = $database; host = $host);
$connect = DBI-> connect($dsn, $user, $pass,{printError =>1}) or die $DBI::errstr;
my $query = $connect->prepare(qq(Select c.Rna_sequence_sequence, c.clone_name, p.idproject, p.description, h.hit_start, h.hit_end, h.hit_string from Cloned_rna c, Project p, Hsp h where c.Rna_sequence_sequence = h.Rna_sequence_sequence and c.Project_idproject = p.idproject and c.Project_idproject = 72));
$query-> execute;
while (my @hit = $query->fetchrow_array()){
print "$hit[0]: $hit[1]: $hit[2]: $hit[3]: $hit[4]: $hit[5]:$hit[6]<br>";

the error i get are::
DBD::mysql::st execute failed: No database selected at line 12.
DBD::mysql::st fetchrow_array failed: fetch() without execute() at line 13.

and further am loging in to the database as a' root 'which doesnt have a  password. Is that the way i have done is right or should i have to omit the password?
could any one help me  out of this.

thanks in advance.

Posted by admin (Graham Ellis), 27 September 2007
Try something like


Your use of "database =" within the string is something that I have not used and may be causing problems.

Also check your return statuses to see where the program goes wrong;  as it stands at the moment you assuming everyting  works correctly and blundering onwards ...

Posted by KevinAD (KevinAD), 27 September 2007
As far as I know, the use of "=" in the connection string is OK.

Not sure what the problem is.

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