diff --git a/src/database/database.rs b/src/database/database.rs
index 119217c..273ecdd 100644
--- a/src/database/database.rs
+++ b/src/database/database.rs
@@ -15,11 +15,10 @@ impl Database {
 
         let namespace_cf = ColumnFamilyDescriptor::new("NamespaceData", Options::default());
         let table_cf = ColumnFamilyDescriptor::new("TableData", Options::default());
-        let operator_cf = ColumnFamilyDescriptor::new("OperatorStatistics", Options::default());
         let table_namespace_cf =
             ColumnFamilyDescriptor::new("TableNamespaceMap", Options::default());
 
-        let cfs_vec = vec![namespace_cf, table_cf, operator_cf, table_namespace_cf];
+        let cfs_vec = vec![namespace_cf, table_cf,  table_namespace_cf];
 
         let db = DB::open_cf_descriptors(&opts, path, cfs_vec)
             .map_err(|e| std::io::Error::new(std::io::ErrorKind::Other, e.to_string()))?;
diff --git a/src/dto/operator_statistics.rs b/src/dto/operator_statistics.rs
deleted file mode 100644
index cb7b7d9..0000000
--- a/src/dto/operator_statistics.rs
+++ /dev/null
@@ -1,33 +0,0 @@
-use serde::{Deserialize, Serialize};
-
-#[derive(Debug, Serialize, Deserialize)]
-pub struct OperatorStatistics {
-    pub operator_string: String,
-    pub cardinality_prev_result: u64,
-}
-
-#[cfg(test)]
-mod tests {
-    use super::*;
-
-    #[test]
-    fn test_operator_statistics_serialization() {
-        let operator_statistics = OperatorStatistics {
-            operator_string: "test_operator".to_string(),
-            cardinality_prev_result: 100,
-        };
-
-        let serialized = serde_json::to_string(&operator_statistics).unwrap();
-        let expected = r#"{"operator_string":"test_operator","cardinality_prev_result":100}"#;
-        assert_eq!(serialized, expected);
-    }
-
-    #[test]
-    fn test_operator_statistics_deserialization() {
-        let data = r#"{"operator_string":"test_operator","cardinality_prev_result":100}"#;
-        let operator_statistics: OperatorStatistics = serde_json::from_str(data).unwrap();
-
-        assert_eq!(operator_statistics.operator_string, "test_operator");
-        assert_eq!(operator_statistics.cardinality_prev_result, 100);
-    }
-}