Re: Problem with DBI and placeholders

The ? is for quoting field values rather than entering table or field
names. "SELECT * FROM $table" is probably what you want.

On Fri, Apr 9, 2021 at 12:49 PM mailing lists via beginners <
[email protected]> wrote:

> Hello,
>
> I am having a problem with a very simple task and I don't see where the
> fault is.
>
> The first query works with problem but the second one fails with this
> error:
>
>  ./test.pl
> OK 1
> DBD::mysql::st execute failed: You have an error in your SQL syntax; check
> the manual that corresponds to your MySQL server version for the right
> syntax to use near ''test'' at line 1 at ./test.pl line 28.
> END
>
>
> Does anyone know where the problem is?
>
>
>      1    #!/usr/bin/perl
>      2    use strict;
>      3    use warnings;
>      4    use 5.010;
>      5    use DBI;
>      6
>      7    my %db = (
>      8       host     => 'mysql.local',
>      9       user     => 'app',
>     10       password => '12345678',
>     11       db       => 'test_db',
>     12    );
>     13
>     14    my $dbh = DBI->connect(
>     15
> 'dbi:mysql:database='.$db{'db'}.';host='.$db{'host'}.';port=3306',
>     16                                $db{'user'},
>     17                                $db{'password'},
>     18                                { AutoCommit => 1, },
>     19                              )
>     20                  or die "Can't connect to database: $DBI::errstr\n";
>     21
>     22
>     23    my $sth = $dbh->prepare("SELECT * FROM test");
>     24    $sth->execute() && say "OK 1";
>     25
>     26    my $table="test";
>     27    $sth = $dbh->prepare("SELECT * FROM ?");
>     28    $sth->execute($table) && say "OK 2"
>     29
>     30    say "END";
>
>
>
>
>

-- 
Andrew Solomon
Director, Geekuni <https://geekuni.com/>
P: +44 7931 946 062
E: [email protected]