diff --git a/Cargo.toml b/Cargo.toml
index c2d8bff5..3d089da5 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -33,6 +33,7 @@ harness = false
 
 [dependencies]
 ahash                 = { version = "0.8.11" }
+async-lock            = { version = "3.3.0" }
 async-trait           = { version = "0.1.77", optional = true }
 bincode               = { version = "1.3.3" }
 bytes                 = { version = "1.5.0" }
@@ -50,7 +51,6 @@ kip_db                = { version = "0.1.2-alpha.25.fix2" }
 lazy_static           = { version = "1.4.0" }
 log                   = { version = "0.4.21", optional = true }
 ordered-float         = { version = "4.2.0" }
-parking_lot           = { version = "0.12.1" }
 petgraph              = { version = "0.6.4" }
 pgwire                = { version = "0.19.2", optional = true }
 rand                  = { version = "0.9.0-alpha.0" }
diff --git a/src/binder/copy.rs b/src/binder/copy.rs
index 58160289..64613a5c 100644
--- a/src/binder/copy.rs
+++ b/src/binder/copy.rs
@@ -97,10 +97,7 @@ impl<'a, T: Transaction> Binder<'a, T> {
                 ))
             }
         } else {
-            Err(DatabaseError::InvalidTable(format!(
-                "not found table {}",
-                table_name
-            )))
+            Err(DatabaseError::TableNotFound)
         }
     }
 }
diff --git a/src/binder/mod.rs b/src/binder/mod.rs
index 76836dbe..9919a09f 100644
--- a/src/binder/mod.rs
+++ b/src/binder/mod.rs
@@ -34,6 +34,32 @@ pub enum InputRefType {
     GroupBy,
 }
 
+pub enum CommandType {
+    DQL,
+    DML,
+    DDL,
+}
+
+pub fn command_type(stmt: &Statement) -> Result<CommandType, DatabaseError> {
+    match stmt {
+        Statement::CreateTable { .. }
+        | Statement::CreateIndex { .. }
+        | Statement::AlterTable { .. }
+        | Statement::Drop { .. } => Ok(CommandType::DDL),
+        Statement::Query(_)
+        | Statement::Explain { .. }
+        | Statement::ExplainTable { .. }
+        | Statement::ShowTables { .. } => Ok(CommandType::DQL),
+        Statement::Analyze { .. }
+        | Statement::Truncate { .. }
+        | Statement::Update { .. }
+        | Statement::Delete { .. }
+        | Statement::Insert { .. }
+        | Statement::Copy { .. } => Ok(CommandType::DML),
+        stmt => Err(DatabaseError::UnsupportedStmt(stmt.to_string())),
+    }
+}
+
 // Tips: only query now!
 #[derive(Debug, Copy, Clone, Hash, Eq, PartialEq)]
 pub enum QueryBindStep {
diff --git a/src/db.rs b/src/db.rs
index ea67f3fe..98a9f8b0 100644
--- a/src/db.rs
+++ b/src/db.rs
@@ -1,9 +1,11 @@
 use ahash::HashMap;
+use async_lock::{RwLock, RwLockReadGuardArc, RwLockWriteGuardArc};
+use sqlparser::ast::Statement;
 use std::path::PathBuf;
 use std::sync::atomic::AtomicUsize;
 use std::sync::Arc;
 
-use crate::binder::{Binder, BinderContext};
+use crate::binder::{command_type, Binder, BinderContext, CommandType};
 use crate::errors::DatabaseError;
 use crate::execution::volcano::{build_write, try_collect};
 use crate::expression::function::{FunctionSummary, ScalarFunctionImpl};
@@ -19,6 +21,12 @@ use crate::types::tuple::{SchemaRef, Tuple};
 
 pub(crate) type Functions = HashMap<FunctionSummary, Arc<dyn ScalarFunctionImpl>>;
 
+#[allow(dead_code)]
+pub(crate) enum MetaDataLock {
+    Read(RwLockReadGuardArc<()>),
+    Write(RwLockWriteGuardArc<()>),
+}
+
 pub struct DataBaseBuilder {
     path: PathBuf,
     functions: Functions,
@@ -45,6 +53,7 @@ impl DataBaseBuilder {
         Ok(Database {
             storage,
             functions: Arc::new(self.functions),
+            mdl: Arc::new(RwLock::new(())),
         })
     }
 }
@@ -52,6 +61,7 @@ impl DataBaseBuilder {
 pub struct Database<S: Storage> {
     pub storage: S,
     functions: Arc<Functions>,
+    mdl: Arc<RwLock<()>>,
 }
 
 impl<S: Storage> Database<S> {
@@ -60,8 +70,19 @@ impl<S: Storage> Database<S> {
         &self,
         sql: T,
     ) -> Result<(SchemaRef, Vec<Tuple>), DatabaseError> {
+        // parse
+        let stmts = parse_sql(sql)?;
+        if stmts.is_empty() {
+            return Err(DatabaseError::EmptyStatement);
+        }
+        let stmt = &stmts[0];
+        let _guard = if matches!(command_type(stmt)?, CommandType::DDL) {
+            MetaDataLock::Write(self.mdl.write_arc().await)
+        } else {
+            MetaDataLock::Read(self.mdl.read_arc().await)
+        };
         let transaction = self.storage.transaction().await?;
-        let plan = Self::build_plan::<T, S::TransactionType>(sql, &transaction, &self.functions)?;
+        let plan = Self::build_plan(stmt, &transaction, &self.functions)?;
 
         Self::run_volcano(transaction, plan).await
     }
@@ -81,24 +102,21 @@ impl<S: Storage> Database<S> {
     }
 
     pub async fn new_transaction(&self) -> Result<DBTransaction<S>, DatabaseError> {
+        let guard = self.mdl.read_arc().await;
         let transaction = self.storage.transaction().await?;
 
         Ok(DBTransaction {
             inner: transaction,
             functions: self.functions.clone(),
+            _guard: guard,
         })
     }
 
-    pub fn build_plan<V: AsRef<str>, T: Transaction>(
-        sql: V,
+    pub(crate) fn build_plan(
+        stmt: &Statement,
         transaction: &<S as Storage>::TransactionType,
         functions: &Functions,
     ) -> Result<LogicalPlan, DatabaseError> {
-        // parse
-        let stmts = parse_sql(sql)?;
-        if stmts.is_empty() {
-            return Err(DatabaseError::EmptyStatement);
-        }
         let mut binder = Binder::new(
             BinderContext::new(transaction, functions, Arc::new(AtomicUsize::new(0))),
             None,
@@ -110,7 +128,7 @@ impl<S: Storage> Database<S> {
         ///   Sort(a)
         ///     Limit(1)
         ///       Project(a,b)
-        let source_plan = binder.bind(&stmts[0])?;
+        let source_plan = binder.bind(stmt)?;
         // println!("source_plan plan: {:#?}", source_plan);
 
         let best_plan =
@@ -200,6 +218,7 @@ impl<S: Storage> Database<S> {
 pub struct DBTransaction<S: Storage> {
     inner: S::TransactionType,
     functions: Arc<Functions>,
+    _guard: RwLockReadGuardArc<()>,
 }
 
 impl<S: Storage> DBTransaction<S> {
@@ -207,8 +226,18 @@ impl<S: Storage> DBTransaction<S> {
         &mut self,
         sql: T,
     ) -> Result<(SchemaRef, Vec<Tuple>), DatabaseError> {
-        let mut plan =
-            Database::<S>::build_plan::<T, S::TransactionType>(sql, &self.inner, &self.functions)?;
+        let stmts = parse_sql(sql)?;
+        if stmts.is_empty() {
+            return Err(DatabaseError::EmptyStatement);
+        }
+        let stmt = &stmts[0];
+        if matches!(command_type(stmt)?, CommandType::DDL) {
+            return Err(DatabaseError::UnsupportedStmt(
+                "`DDL` is not allowed to execute within a transaction".to_string(),
+            ));
+        }
+        let mut plan = Database::<S>::build_plan(stmt, &self.inner, &self.functions)?;
+
         let schema = plan.output_schema().clone();
         let mut stream = build_write(plan, &mut self.inner);
 
@@ -298,20 +327,17 @@ mod test {
         let temp_dir = TempDir::new().expect("unable to create temporary working directory");
         let fnck_sql = DataBaseBuilder::path(temp_dir.path()).build().await?;
 
-        let mut tx_1 = fnck_sql.new_transaction().await?;
-        let mut tx_2 = fnck_sql.new_transaction().await?;
-
-        let _ = tx_1
+        let _ = fnck_sql
             .run("create table t1 (a int primary key, b int)")
             .await?;
-        let _ = tx_2
-            .run("create table t1 (c int primary key, d int)")
-            .await?;
+
+        let mut tx_1 = fnck_sql.new_transaction().await?;
+        let mut tx_2 = fnck_sql.new_transaction().await?;
 
         let _ = tx_1.run("insert into t1 values(0, 0)").await?;
         let _ = tx_1.run("insert into t1 values(1, 1)").await?;
 
-        let _ = tx_2.run("insert into t1 values(2, 2)").await?;
+        let _ = tx_2.run("insert into t1 values(0, 0)").await?;
         let _ = tx_2.run("insert into t1 values(3, 3)").await?;
 
         let (_, tuples_1) = tx_1.run("select * from t1").await?;
@@ -338,8 +364,8 @@ mod test {
         assert_eq!(
             tuples_2[0].values,
             vec![
-                Arc::new(DataValue::Int32(Some(2))),
-                Arc::new(DataValue::Int32(Some(2)))
+                Arc::new(DataValue::Int32(Some(0))),
+                Arc::new(DataValue::Int32(Some(0)))
             ]
         );
         assert_eq!(
@@ -354,6 +380,10 @@ mod test {
 
         assert!(tx_2.commit().await.is_err());
 
+        let mut tx_3 = fnck_sql.new_transaction().await?;
+        let res = tx_3.run("create table t2 (a int primary key, b int)").await;
+        assert!(res.is_err());
+
         Ok(())
     }
 }
diff --git a/src/storage/kip.rs b/src/storage/kip.rs
index 323989ad..d71ee85e 100644
--- a/src/storage/kip.rs
+++ b/src/storage/kip.rs
@@ -23,6 +23,7 @@ use std::sync::Arc;
 pub struct KipStorage {
     pub inner: Arc<storage::KipStorage>,
     pub(crate) meta_cache: Arc<StatisticsMetaCache>,
+    pub(crate) table_cache: Arc<ShardingLruCache<String, TableCatalog>>,
 }
 
 impl KipStorage {
@@ -31,10 +32,12 @@ impl KipStorage {
             storage::KipStorage::open_with_config(Config::new(path).enable_level_0_memorization())
                 .await?;
         let meta_cache = Arc::new(ShardingLruCache::new(128, 16, RandomState::new()).unwrap());
+        let table_cache = Arc::new(ShardingLruCache::new(128, 16, RandomState::new()).unwrap());
 
         Ok(KipStorage {
             inner: Arc::new(storage),
             meta_cache,
+            table_cache,
         })
     }
 }
@@ -47,7 +50,7 @@ impl Storage for KipStorage {
 
         Ok(KipTransaction {
             tx,
-            table_cache: ShardingLruCache::new(8, 2, RandomState::default())?,
+            table_cache: Arc::clone(&self.table_cache),
             meta_cache: self.meta_cache.clone(),
         })
     }
@@ -57,7 +60,7 @@ pub(crate) type StatisticsMetaCache = ShardingLruCache<(TableName, IndexId), Sta
 
 pub struct KipTransaction {
     tx: mvcc::Transaction,
-    table_cache: ShardingLruCache<String, TableCatalog>,
+    table_cache: Arc<ShardingLruCache<String, TableCatalog>>,
     meta_cache: Arc<StatisticsMetaCache>,
 }
 
diff --git a/tests/slt/basic_test.slt b/tests/slt/basic_test.slt
index 34fff868..b584facf 100644
--- a/tests/slt/basic_test.slt
+++ b/tests/slt/basic_test.slt
@@ -86,6 +86,16 @@ select CAST(name AS BIGINT) from t
 statement ok
 select CAST(id AS VARCHAR) from t
 
+statement ok
+create table t1 (id int primary key, name VARCHAR NOT NULL)
+
+# issue: https://github.com/KipData/FnckSQL/issues/175
+statement error
+select t.name from t1;
+
+statement ok
+drop table t1
+
 statement ok
 drop table if exists t