Perl database Add, delete, update, query operations example _perl

Note: When connecting using the database specified by the SID, the database is not specified in the connection.

#!/usr/bin/perl
use strict;
use warnings;
use DBI;
my $db_name="geneva_admin";
my $db_passwd="geneva_admin";

my $dbh=DBI->connect("dbi:Oracle:","$db_name","$db_passwd")
 or die "Can't connect to oracle database:$DBI::errstr\n";
 
my $sth=$dbh->prepare("select a,b
   from a_tmp
   where a=2")
 or die "Can't prepare SQl prepare:$DBI::errstr\n";
$sth->execute or die "Can't execute:$DBI::errstr\n";
while (my @row = $sth->fetchrow_array()){
 my ($a,$b) = @row;
 print "1..\$a=$a,\$b=$b\n";
}
$sth->finish();
my $row=3;
my $sql="select a,b
 from a_tmp
 where a = ?";
$sth=$dbh->prepare($sql) or die "Can't prepare SQl prepare:$DBI::errstr\n";
$sth->execute($row) or die "Can't execute:$DBI::errstr\n";
while (my @row = $sth->fetchrow_array()){
 my ($a,$b) = @row;
 print "2..\$a=$a,\$b=$b\n";
}
$sth->finish();
my $row_a=3;
my $row_c=0;
$sql="select a,b
 from a_tmp
 where a = ?
 and  c = ?";
$sth=$dbh->prepare($sql) or die "Can't prepare SQl prepare:$DBI::errstr\n";
$sth->execute($row_a,$row_c) or die "Can't execute:$DBI::errstr\n";
while (my @row = $sth->fetchrow_array()){
 my ($a,$b) = @row;
 print "3..\$a=$a,\$b=$b\n";
}
$sth->finish();
for $row(1,2,3){
$sql="select a,b
 from a_tmp
 where a = ?";
$sth=$dbh->prepare($sql) or die "Can't prepare SQl prepare:$DBI::errstr\n";
$sth->execute($row) or die "Can't execute:$DBI::errstr\n";
while (my @row = $sth->fetchrow_array()){
 my ($a,$b) = @row;
 print "4..\$a=$a,\$b=$b\n";
}
}
$sth->finish();
#for $row(1,2,3){
#$sql="insert into a_tmp
#   values (?,?,?)";
#$sth=$dbh->prepare($sql) or die "Can't prepare SQl prepare:$DBI::errstr\n";
#$sth->execute($row,$row+1,$row+2) or die "Can't execute:$DBI::errstr\n";
#}
##$dbh->commit;
#$sth->finish();

#$sql="insert into a_tmp
#   values (100,30,2)";
#$sth=$dbh->prepare($sql) or die "Can't prepare SQl prepare:$DBI::errstr\n";
#$sth->execute or die "Can't execute:$DBI::errstr\n";
##$dbh->commit;
#$sth->finish();
for $row(1,2,3){
$sql="update a_tmp 
   set b = ?
    , c = ?
   where a = ?";
$sth=$dbh->prepare($sql) or die "Can't prepare SQl prepare:$DBI::errstr\n";
$sth->execute($row+100,$row+50,$row) or die "Can't execute:$DBI::errstr\n";
}
#$dbh->commit;
$sth->finish();

for $row(1,2,3){
$sql="delete from a_tmp
   where c=2";
$sth=$dbh->prepare($sql) or die "Can't prepare SQl prepare:$DBI::errstr\n";
$sth->execute or die "Can't execute:$DBI::errstr\n";
}
#$dbh->commit;
$sth->finish();

$dbh->do("insert into a_tmp values (1,1,1)") or die "$DBI::errstr\n";
$dbh->do("delete from a_tmp where c=51")   or die "$DBI::errstr\n";
#$dbh->commit;
$sth->finish();
$dbh->disconnect;