#############################################################################
sub wish_to_adjust_options_for_tables {
        my ($options) = @_;
         
        $options -> {key} = ['name'];
        $options -> {default_storage_engine} = $preconf -> {db_default_storage_engine};
}
#############################################################################
sub wish_to_clarify_demands_for_tables {
        my ($i, $options) = @_;
                 
        my %def = (
                name    => $i -> {name},
                 
                REMARKS => $i -> {REMARKS} || $i -> {label},
        );
         
        my %columns = %{$i -> {columns}};
         
        while (my ($k, $v) = each %columns) {
         
                $v -> {_PK} or next;
                 
                $def {pk} = {name => $k, %$v};
                 
                last;
         
        }
         
        %$i = %def;
}
################################################################################
sub wish_to_explore_existing_tables {
        my ($options) = @_;
        my $existing = {};
        sql_select_loop (
                 
                q {select table_name, table_comment from information_schema.tables where table_schema=database()}, 
                 
                sub {
                        $existing -> {$i -> {table_name}} = {
                         
                                name    => $i -> {table_name},
                         
                                REMARKS => length $i -> {table_comment} ? $i -> {table_comment} : undef,
                                 
                        };
                                         
                },
        );
        return $existing;
}
#############################################################################
sub wish_to_update_demands_for_tables {
        my ($old, $new, $options) = @_;
        foreach my $i ($old, $new) {
                         
                %$i = map {$_ => $i -> {$_}} qw (name REMARKS);
        }
}
#############################################################################
sub wish_to_schedule_modifications_for_tables {
        my ($old, $new, $todo, $options) = @_;
        push @{$todo -> {comment}}, $new;
}
#############################################################################
sub wish_to_actually_comment_tables {
        my ($items, $options) = @_;
         
        foreach my $i (@$items) {
         
                ($i -> {REMARKS} ||= '') =~ s{'}{''}g; #'
                sql_do (qq {ALTER TABLE $i->{name} COMMENT '$i->{REMARKS}'});
                 
        }
}
#############################################################################
sub wish_to_actually_create_tables {
        my ($items, $options) = @_;
         
        foreach my $i (@$items) {       
                 
                sql_do (qq {CREATE TABLE $i->{name} ($i->{pk}->{name} INT $i->{pk}->{_EXTRA} PRIMARY KEY)} . ($options -> {default_storage_engine} ? qq { ENGINE=$options->{default_storage_engine}} : ''));
                 
        }
         
        wish_to_actually_comment_tables ([grep {$_ -> {REMARKS}} @$items], $options);
}
1;