diff --git a/src/data_type/function.rs b/src/data_type/function.rs
index cfc9637f..5f1e40d9 100644
--- a/src/data_type/function.rs
+++ b/src/data_type/function.rs
@@ -9,7 +9,6 @@ use std::{
     result,
     sync::{Arc, Mutex},
 };
-use regex::bytes::Regex;
 use itertools::Itertools;
 
 use super::{
diff --git a/tests/integration.rs b/tests/integration.rs
index f48ef049..206a1336 100644
--- a/tests/integration.rs
+++ b/tests/integration.rs
@@ -90,6 +90,7 @@ const QUERIES: &[&str] = &[
     SELECT * FROM t1 UNION SELECT * FROM t2",
     // Some joins
     "SELECT * FROM order_table LEFT JOIN item_table on id=order_id WHERE price>10",
+    // Some string functions
     "SELECT UPPER(z) FROM table_2 LIMIT 5",
     "SELECT LOWER(z) FROM table_2 LIMIT 5",
 ];