diff --git a/cozo-rocks/src/lib.rs b/cozo-rocks/src/lib.rs
index 1f14018e..dbc106fe 100644
--- a/cozo-rocks/src/lib.rs
+++ b/cozo-rocks/src/lib.rs
@@ -324,7 +324,7 @@ pub trait DBImpl {
     fn iterator(&self, cf: &ColumnFamilyHandle, options: Option<&ReadOptions>) -> DBIterator;
     fn create_column_family(&self, name: impl AsRef<str>) -> Result<()>;
     fn drop_column_family(&self, name: impl AsRef<str>) -> Result<()>;
-    fn get_column_family_names(&self) -> Vec<String>;
+    fn all_cf_names(&self) -> Vec<String>;
     fn get(&self, key: impl AsRef<[u8]>, cf: &ColumnFamilyHandle, options: Option<&ReadOptions>)
            -> Result<Option<PinnableSlice>>;
     fn put(&self, key: impl AsRef<[u8]>, val: impl AsRef<[u8]>, cf: &ColumnFamilyHandle, options: Option<&WriteOptions>)
@@ -398,7 +398,7 @@ impl DBImpl for DB {
         }
     }
 
-    fn get_column_family_names(&self) -> Vec<String> {
+    fn all_cf_names(&self) -> Vec<String> {
         self.inner.get_column_family_names_raw().iter().map(|v| v.to_string_lossy().to_string()).collect()
     }
 
diff --git a/src/definition.rs b/src/definition.rs
index 527011d0..c18f2196 100644
--- a/src/definition.rs
+++ b/src/definition.rs
@@ -46,7 +46,7 @@ fn parse_col_name(pair: Pair<Rule>) -> Result<(String, bool)> {
 
 
 impl StructuredEnvItem {
-    pub fn build_edge_def(&mut self, pair: Pair<Rule>, global: bool) -> Result<String> {
+    pub fn build_edge_def(&mut self, pair: Pair<Rule>, local_id: usize) -> Result<String> {
         let mut inner = pair.into_inner();
         let src_name = build_name_in_def(inner.next().unwrap(), true)?;
         let src = self.resolve(&src_name).ok_or(UndefinedType)?;
@@ -63,7 +63,7 @@ impl StructuredEnvItem {
         } else {
             return Err(WrongType);
         };
-        if global && (!src_id.global || !dst_id.global) {
+        if local_id == 0 && (!src_id.is_global() || !dst_id.is_global()) {
             return Err(IncompatibleEdge);
         }
         let (keys, cols) = if let Some(p) = inner.next() {
@@ -71,7 +71,7 @@ impl StructuredEnvItem {
         } else {
             (vec![], vec![])
         };
-        let table_id = TableId { name: name.clone(), global };
+        let table_id = TableId { name: name.clone(), local_id };
         let edge = Edge {
             status: Planned,
             src: src_id,
@@ -97,11 +97,11 @@ impl StructuredEnvItem {
             Err(NameConflict)
         }
     }
-    pub fn build_node_def(&mut self, pair: Pair<Rule>, global: bool) -> Result<String> {
+    pub fn build_node_def(&mut self, pair: Pair<Rule>, local_id: usize) -> Result<String> {
         let mut inner = pair.into_inner();
         let name = build_name_in_def(inner.next().unwrap(), true)?;
         let (keys, cols) = self.build_col_defs(inner.next().unwrap())?;
-        let table_id = TableId { name: name.clone(), global };
+        let table_id = TableId { name: name.clone(), local_id };
         let node = Node {
             status: Planned,
             id: table_id,
@@ -125,7 +125,7 @@ impl StructuredEnvItem {
         }
         Ok(ret)
     }
-    fn build_columns_def(&mut self, pair: Pair<Rule>, global: bool) -> Result<String> {
+    fn build_columns_def(&mut self, pair: Pair<Rule>, local_id: usize) -> Result<String> {
         let mut inner = pair.into_inner();
         let name = build_name_in_def(inner.next().unwrap(), true)?;
         let node_name = build_name_in_def(inner.next().unwrap(), true)?;
@@ -141,8 +141,8 @@ impl StructuredEnvItem {
         if !keys.is_empty() {
             return Err(UnexpectedIndexColumns);
         }
-        let table_id = TableId { name: name.clone(), global };
-        if table_id.global && !node_id.global {
+        let table_id = TableId { name: name.clone(), local_id };
+        if table_id.is_global() && !node_id.is_global() {
             return Err(IncompatibleEdge);
         }
 
@@ -158,7 +158,7 @@ impl StructuredEnvItem {
         }
     }
 
-    fn build_index_def(&mut self, pair: Pair<Rule>, global: bool) -> Result<String> {
+    fn build_index_def(&mut self, pair: Pair<Rule>, local_id: usize) -> Result<String> {
         let mut inner = pair.into_inner();
         let mut name = build_name_in_def(inner.next().unwrap(), true)?;
         let node_name;
@@ -188,9 +188,9 @@ impl StructuredEnvItem {
         } else {
             return Err(WrongType);
         };
-        let table_id = TableId { name: name.clone(), global };
+        let table_id = TableId { name: name.clone(), local_id };
 
-        if table_id.global && !node_id.global {
+        if table_id.is_global() && !node_id.is_global() {
             return Err(IncompatibleEdge);
         }
 
@@ -303,10 +303,10 @@ impl RocksStorage {
             let v = it.value();
             let mut key_parser = ByteArrayParser::new(&k);
             let mut data_parser = ByteArrayParser::new(&v);
-
+            key_parser.parse_varint().unwrap();
             let table_name = key_parser.parse_value().unwrap().get_string().unwrap();
             let table_kind = data_parser.parse_value().unwrap();
-            let table_id = TableId { name: table_name, global: true };
+            let table_id = TableId { name: table_name, local_id: 0 };
 
             match table_kind {
                 Value::UInt(i) if i == TableKind::Node as u64 => {
@@ -350,8 +350,8 @@ impl RocksStorage {
                 Value::UInt(i) if i == TableKind::Edge as u64 => {
                     let src_name = data_parser.parse_value().unwrap().get_string().unwrap();
                     let dst_name = data_parser.parse_value().unwrap().get_string().unwrap();
-                    let src_id = TableId { name: src_name, global: true };
-                    let dst_id = TableId { name: dst_name, global: true };
+                    let src_id = TableId { name: src_name, local_id: 0 };
+                    let dst_id = TableId { name: dst_name, local_id: 0 };
                     let keys: Vec<_> = data_parser.parse_value().unwrap().get_list().unwrap()
                         .into_iter().map(|v| {
                         let mut vs = v.get_list().unwrap().into_iter();
@@ -404,6 +404,7 @@ impl RocksStorage {
 
     fn persist_node(&mut self, node: &mut Node) -> Result<()> {
         let mut key_writer = ByteArrayBuilder::with_capacity(8);
+        key_writer.build_varint(0);
         key_writer.build_value(&Value::RefString(&node.id.name));
         let mut val_writer = ByteArrayBuilder::with_capacity(128);
         val_writer.build_value(&Value::UInt(TableKind::Node as u64));
@@ -429,6 +430,7 @@ impl RocksStorage {
 
     fn persist_edge(&mut self, edge: &mut Edge) -> Result<()> {
         let mut key_writer = ByteArrayBuilder::with_capacity(8);
+        key_writer.build_varint(0);
         key_writer.build_value(&Value::RefString(&edge.id.name));
 
         let mut val_writer = ByteArrayBuilder::with_capacity(128);
@@ -500,6 +502,7 @@ impl Evaluator<RocksStorage> {
                 r @ (Rule::global_def | Rule::local_def) => {
                     let inner = pair.into_inner().next().unwrap();
                     let global = r == Rule::global_def;
+                    let local_id = self.get_next_local_id(global);
                     let env_to_build = if global {
                         self.s_envs.root_mut()
                     } else {
@@ -507,16 +510,16 @@ impl Evaluator<RocksStorage> {
                     };
                     new_tables.push((global, match inner.as_rule() {
                         Rule::node_def => {
-                            env_to_build.build_node_def(inner, global)?
+                            env_to_build.build_node_def(inner, local_id)?
                         }
                         Rule::edge_def => {
-                            env_to_build.build_edge_def(inner, global)?
+                            env_to_build.build_edge_def(inner, local_id)?
                         }
                         Rule::columns_def => {
-                            env_to_build.build_columns_def(inner, global)?
+                            env_to_build.build_columns_def(inner, local_id)?
                         }
                         Rule::index_def => {
-                            env_to_build.build_index_def(inner, global)?
+                            env_to_build.build_index_def(inner, local_id)?
                         }
                         _ => todo!()
                     }));
diff --git a/src/eval.rs b/src/eval.rs
index 78c0a14e..ae166940 100644
--- a/src/eval.rs
+++ b/src/eval.rs
@@ -1,3 +1,5 @@
+use std::sync::Arc;
+use std::sync::atomic::{AtomicUsize, Ordering};
 use crate::ast::Expr;
 use crate::ast::Expr::*;
 use crate::error::Result;
@@ -11,6 +13,17 @@ use crate::storage::{DummyStorage, RocksStorage, Storage};
 pub struct Evaluator<S: Storage> {
     pub s_envs: StructuredEnv,
     pub storage: S,
+    pub last_local_id: Arc<AtomicUsize>,
+}
+
+impl <S:Storage> Evaluator<S> {
+    pub fn get_next_local_id(&self, is_global: bool) -> usize {
+        if is_global {
+            0
+        } else {
+            self.last_local_id.fetch_add(1, Ordering::Relaxed)
+        }
+    }
 }
 
 pub type EvaluatorWithStorage = Evaluator<RocksStorage>;
@@ -18,13 +31,21 @@ pub type BareEvaluator = Evaluator<DummyStorage>;
 
 impl EvaluatorWithStorage {
     pub fn new(path: String) -> Result<Self> {
-        Ok(Self { s_envs: StructuredEnv::new(), storage: RocksStorage::new(path)? })
+        Ok(Self {
+            s_envs: StructuredEnv::new(),
+            storage: RocksStorage::new(path)?,
+            last_local_id: Arc::new(AtomicUsize::new(1)),
+        })
     }
 }
 
 impl Default for BareEvaluator {
     fn default() -> Self {
-        Self { s_envs: StructuredEnv::new(), storage: DummyStorage }
+        Self {
+            s_envs: StructuredEnv::new(),
+            storage: DummyStorage,
+            last_local_id: Arc::new(AtomicUsize::new(0)),
+        }
     }
 }
 
diff --git a/src/storage.rs b/src/storage.rs
index f54b3a51..c201ff79 100644
--- a/src/storage.rs
+++ b/src/storage.rs
@@ -86,7 +86,7 @@ mod tests {
         builder.build_value(&Value::RefString("Another key"));
         let key2 = builder;
         let cf = db.get_cf_handle("default").unwrap();
-        println!("{:?}", db.get_column_family_names());
+        println!("{:?}", db.all_cf_names());
 
         let val = db.get(&key, &cf, None).unwrap();
         println!("before anything {}", val.is_none());
diff --git a/src/typing.rs b/src/typing.rs
index e8ab2b68..dcbc90f6 100644
--- a/src/typing.rs
+++ b/src/typing.rs
@@ -55,16 +55,24 @@ pub enum StorageStatus {
 }
 
 #[derive(PartialEq, Eq, Ord, PartialOrd, Clone)]
-pub struct TableId{
+pub struct TableId {
     pub name: String,
-    pub global: bool
+    pub local_id: usize,
+}
+
+impl TableId {
+    pub fn is_global(&self) -> bool {
+        self.local_id == 0
+    }
 }
 
 
 impl Debug for TableId {
     fn fmt(&self, f: &mut Formatter<'_>) -> std::fmt::Result {
-        f.write_str( if self.global { "+" } else {"-"})?;
         f.write_str(&self.name)?;
+        if self.local_id > 0 {
+            f.write_str(&format!("({})", self.local_id))?;
+        }
         Ok(())
     }
 }
diff --git a/src/value.rs b/src/value.rs
index d566ed1b..26c43992 100644
--- a/src/value.rs
+++ b/src/value.rs
@@ -343,7 +343,7 @@ pub struct ByteArrayBuilder<T: Write + AsRef<[u8]>> {
     byte_writer: T,
 }
 
-impl <T: Write + AsRef<[u8]>> AsRef<[u8]> for ByteArrayBuilder<T> {
+impl<T: Write + AsRef<[u8]>> AsRef<[u8]> for ByteArrayBuilder<T> {
     fn as_ref(&self) -> &[u8] {
         self.byte_writer.as_ref()
     }
@@ -421,7 +421,7 @@ impl<T: Write + AsRef<[u8]>> ByteArrayBuilder<T> {
         self
     }
 
-    pub fn build_value(&mut self, v: &Value) -> &mut Self{
+    pub fn build_value(&mut self, v: &Value) -> &mut Self {
         use ValueTag::*;
 
         match v {
@@ -477,8 +477,14 @@ impl<T: Write + AsRef<[u8]>> ByteArrayBuilder<T> {
 
 
 pub fn cozo_comparator_v1(a: &[u8], b: &[u8]) -> i8 {
-    match cmp_data(&mut ByteArrayParser { bytes: a, current: 0 },
-                   &mut ByteArrayParser { bytes: b, current: 0 }) {
+    let mut ba = &mut ByteArrayParser { bytes: a, current: 0 };
+    let mut bb = &mut ByteArrayParser { bytes: b, current: 0 };
+    match ba.compare_varint(&mut bb) {
+        Less => return -1,
+        Greater => return 1,
+        Equal => {}
+    }
+    match cmp_data(&mut ba, &mut bb) {
         Less => -1,
         Equal => 0,
         Greater => 1