diff --git a/src/data/id.rs b/src/data/id.rs
index 7e61cab..d98c3a0 100644
--- a/src/data/id.rs
+++ b/src/data/id.rs
@@ -1,3 +1,4 @@
+use crate::data::record::{Field, FieldRecord};
 use std::fmt;
 use uuid::Uuid;
 
@@ -14,12 +15,37 @@ impl ID {
     }
 }
 
+impl FieldRecord for ID {
+    fn new_field() -> Field {
+        Field::ID(ID::new())
+    }
+}
+
 impl fmt::Display for ID {
     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
         write!(f, "{}", self.data)
     }
 }
 
+#[cfg(test)]
+mod fielddata {
+    use super::*;
+
+    #[test]
+    fn new_ids_are_unique() {
+        let mut ids: Vec<String> = Vec::new();
+        for _ in 1..10 {
+            match ID::new_field() {
+                Field::ID(id) => {
+                    let id_string = id.to_string();
+                    assert!(!ids.contains(&id_string), "'{}' repeated", id_string);
+                    ids.push(id_string);
+                },
+            }
+        }
+    }
+}
+
 #[cfg(test)]
 mod id {
     use super::*;
diff --git a/src/data/mod.rs b/src/data/mod.rs
index 3ed5f54..6a8279d 100644
--- a/src/data/mod.rs
+++ b/src/data/mod.rs
@@ -1,66 +1,20 @@
-mod id;
+pub mod id;
+pub mod record;
 
-use id::ID;
-use std::{collections::HashMap, fmt};
+struct Table;
 
-#[derive(Clone)]
-enum Field {
-    ID(ID),
-}
-
-struct Record {
-    data: HashMap<String, Field>,
-}
-
-impl Record {
-    fn new(data: HashMap<String, Field>) -> Self {
-        Self { data: data }
-    }
-
-    fn len(&self) -> usize {
-        self.data.len()
-    }
-
-    fn get(&self, name: &str) -> Field {
-        match self.data.get(name) {
-            Some(data) => data.clone(),
-            None => unreachable!(),
-        }
-    }
-}
-
-impl fmt::Display for Field {
-    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
-        match self {
-            Field::ID(id) => write!(f, "{}", id),
-        }
+impl Table {
+    fn new() -> Self {
+        Self {}
     }
 }
 
 #[cfg(test)]
-mod records {
+mod table {
     use super::*;
 
     #[test]
-    fn new_record() {
-        let data: HashMap<String, Field> = HashMap::new();
-        let rec = Record::new(data);
-        assert_eq!(rec.len(), 0);
-    }
-
-    #[test]
-    fn new_record_more_data() {
-        let a = ID::new();
-        let b = ID::new();
-        let c = ID::new();
-        let mut data: HashMap<String, Field> = HashMap::new();
-        data.insert("a".to_string(), Field::ID(a.clone()));
-        data.insert("b".to_string(), Field::ID(b.clone()));
-        data.insert("c".to_string(), Field::ID(c.clone()));
-        let rec = Record::new(data);
-        assert_eq!(rec.len(), 3);
-        assert_eq!(rec.get("a").to_string(), a.to_string(), "record a");
-        assert_eq!(rec.get("b").to_string(), b.to_string(), "record b");
-        assert_eq!(rec.get("c").to_string(), c.to_string(), "record c");
+    fn new_table() {
+        let tbl = Table::new();
     }
 }
diff --git a/src/data/record.rs b/src/data/record.rs
new file mode 100644
index 0000000..7a3ab1f
--- /dev/null
+++ b/src/data/record.rs
@@ -0,0 +1,68 @@
+use crate::data::id::ID;
+use std::{collections::HashMap, fmt};
+
+#[derive(Clone)]
+pub enum Field {
+    ID(ID),
+}
+
+pub trait FieldRecord {
+    fn new_field() -> Field;
+}
+
+struct Record {
+    data: HashMap<String, Field>,
+}
+
+impl Record {
+    fn new(data: HashMap<String, Field>) -> Self {
+        Self { data: data }
+    }
+
+    fn len(&self) -> usize {
+        self.data.len()
+    }
+
+    fn get(&self, name: &str) -> Field {
+        match self.data.get(name) {
+            Some(data) => data.clone(),
+            None => unreachable!(),
+        }
+    }
+}
+
+impl fmt::Display for Field {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        match self {
+            Field::ID(id) => write!(f, "{}", id),
+        }
+    }
+}
+
+#[cfg(test)]
+mod records {
+    use super::*;
+
+    #[test]
+    fn new_record() {
+        let data: HashMap<String, Field> = HashMap::new();
+        let rec = Record::new(data);
+        assert_eq!(rec.len(), 0);
+    }
+
+    #[test]
+    fn new_record_more_data() {
+        let a = ID::new_field();
+        let b = ID::new_field();
+        let c = ID::new_field();
+        let mut data: HashMap<String, Field> = HashMap::new();
+        data.insert("a".to_string(), a.clone());
+        data.insert("b".to_string(), b.clone());
+        data.insert("c".to_string(), c.clone());
+        let rec = Record::new(data);
+        assert_eq!(rec.len(), 3);
+        assert_eq!(rec.get("a").to_string(), a.to_string(), "record a");
+        assert_eq!(rec.get("b").to_string(), b.to_string(), "record b");
+        assert_eq!(rec.get("c").to_string(), c.to_string(), "record c");
+    }
+}