#############################################################################
sub wish_to_adjust_options_for_table_data {     
        my ($options) = @_;
                 
        $options -> {key} ||= 'id';
        $options -> {key}   = [grep {$_} split /\W/, $options -> {key}];
         
        $options -> {ids}   = -1;
}
#############################################################################
sub wish_to_clarify_demands_for_table_data {    
        my ($i, $options) = @_;
        foreach (keys (%{$options -> {root}})) { $i -> {$_} = $options -> {root} -> {$_} }
        $options -> {ids} .= ",$i->{id}" if defined $i -> {id};
}
#############################################################################
sub wish_to_explore_existing_table_data {       
        my ($options) = @_;
                 
        my $sql = "SELECT * FROM $options->{table} WHERE 1=1";
         
        my @params = ();
         
        foreach my $i (keys %{$options -> {root}}) {
                 
                $sql .= " AND $i = ?";
                         
                push @params, $options -> {root} -> {$i};
        }
         
        $sql .= " AND id IN ($options->{ids})" if $options -> {ids} ne '-1';
         
        my $existing = {};
        my @key = @{$options -> {key}};
                 
        sql_select_loop ($sql, sub { $existing -> {join '_', @$i {@key}} = $i }, @params);
         
        return $existing;
}
#############################################################################
sub wish_to_update_demands_for_table_data {
        my ($old, $new, $options) = @_;
        foreach (keys %$old) {exists  $new -> {$_} or $new -> {$_} = $old -> {$_}};
        foreach (keys %$new) {defined $new -> {$_} and $new -> {$_} .= ''};
}
#############################################################################
sub wish_to_schedule_modifications_for_table_data {     
        my ($old, $new, $todo, $options) = @_;
        push @{$todo -> {update}}, $new;
}
#############################################################################
sub wish_to_schedule_cleanup_for_table_data {   
        my ($existing, $todo, $options) = @_;
         
        %{$options -> {root}} > 0 and %$existing > 0 or return;
                         
        $todo -> {'delete'} = [ values %$existing ];
}
#############################################################################
sub wish_to_actually_create_table_data {        
        my ($items, $options) = @_;
        @$items > 0 or return;
        my @cols = ();
        my @prms = ();
         
        foreach my $col (keys %{$items -> [0]}) {
                push @cols, $col;
                push @prms, [ map {$_ -> {$col}} @$items];
         
        }
                 
        my $sth = $db -> prepare ("INSERT INTO $options->{table} (" . (join ', ', @cols) . ") VALUES (" . (join ', ', map {'?'} @cols) . ")");
        $sth -> execute_array ({}, @prms);
         
        $sth -> finish;
         
}
#############################################################################
sub wish_to_actually_update_table_data {        
        my ($items, $options) = @_;
        @$items > 0 or return;
        my @cols = ();
        my @prms = ();
         
        foreach my $col (grep {$_ ne 'id'} keys %{$items -> [0]}) {
                 
                push @cols, "$col = ?";
                push @prms, [ map {$_ -> {$col}} @$items];
         
        }
         
        push @prms, [ map {$_ -> {id}} @$items];
                 
        my $sth = $db -> prepare ("UPDATE $options->{table} SET " . (join ', ', @cols) . " WHERE id = ?");
        $sth -> execute_array ({}, @prms);
         
        $sth -> finish;
}
#############################################################################
sub wish_to_actually_delete_table_data {
        my ($items, $options) = @_;
         
        @$items > 0 or return;
         
        my $sth = $db -> prepare ("DELETE FROM $options->{table} WHERE id = ?");
         
        $sth -> execute_array ({}, [map {$_ -> {id}} @$items]);
         
        $sth -> finish;
}
1;