--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/Lib/IMPL/SQL/Schema/Column.pm	Mon Nov 09 01:39:31 2009 +0300
@@ -0,0 +1,60 @@
+use strict;
+package IMPL::SQL::Schema::Column;
+use base qw(IMPL::Object IMPL::Object::Autofill);
+
+use IMPL::Class::Property;
+use IMPL::Class::Property::Direct;
+
+BEGIN {
+    public _direct property Name => prop_get;
+    public _direct property Type => prop_get;
+    public _direct property CanBeNull => prop_get;
+    public _direct property DefaultValue => prop_get;
+    public _direct property Tag => prop_get;
+}
+
+__PACKAGE__->PassThroughArgs;
+
+sub CTOR {
+    my $this = shift;
+    
+    $this->{$Name} or die new IMPL::InvalidArgumentException('a column name is required');
+    $this->{$CanBeNull} = 0 if not exists $this->{$CanBeNull};
+    UNIVERSAL::isa($this->{$Type},'IMPL::SQL::Schema::Type') or die new IMPL::InvalidArgumentException('a type is required for the column',$this->{$Name});
+}
+
+sub isEqualsStr {
+    my ($a,$b) = @_;
+    
+    if (defined $a and defined $b) {
+        return $a eq $b;
+    } else {
+        if (defined $a or defined $b) {
+            return 0;
+        } else {
+            return 1;
+        }
+    }
+}
+
+sub isEquals {
+    my ($a,$b) = @_;
+    
+    if (defined $a and defined $b) {
+        return $a == $b;
+    } else {
+        if (defined $a or defined $b) {
+            return 0;
+        } else {
+            return 1;
+        }
+    }
+}
+
+sub isSame {
+    my ($this,$other) = @_;
+    
+    return ($this->{$Name} eq $other->{$Name} and $this->{$CanBeNull} == $other->{$CanBeNull} and isEqualsStr($this->{$DefaultValue}, $other->{$DefaultValue}) and $this->{$Type}->isSame($other->{$Type}));
+}
+
+1;