diff --git a/src/lib.rs b/src/lib.rs
index 5d1bf02..b653377 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -1890,7 +1890,7 @@ mod test {
 
     #[test]
     #[cfg(not(feature = "extra_check"))]
-    fn test_alter_table() -> Result<()> {
+    fn test_alter_table() -> Result<usize> {
         let db = checked_memory_handle();
         db.execute_batch("CREATE TABLE x(t);")?;
         // `execute_batch` should be used but `execute` should also work
diff --git a/src/types/to_sql.rs b/src/types/to_sql.rs
index bd147c3..be88941 100644
--- a/src/types/to_sql.rs
+++ b/src/types/to_sql.rs
@@ -245,7 +245,6 @@ impl<T: ToSql> ToSql for Option<T> {
 #[cfg(test)]
 mod test {
     use super::ToSql;
-    use crate::Result;
 
     fn is_to_sql<T: ToSql>() {}
 
@@ -340,7 +339,7 @@ mod test {
 
     #[cfg(feature = "i128_blob")]
     #[test]
-    fn test_i128() -> Result<()> {
+    fn test_i128() -> crate::Result<()> {
         use crate::Connection;
         use std::i128;
         let db = Connection::open_in_memory()?;
@@ -380,7 +379,7 @@ mod test {
 
     #[cfg(feature = "uuid")]
     #[test]
-    fn test_uuid() -> Result<()> {
+    fn test_uuid() -> crate::Result<()> {
         use crate::{params, Connection};
         use uuid::Uuid;