diff --git a/.github/workflows/rust.yml b/.github/workflows/rust.yml
index 037d21defb..bdfdee20a8 100644
--- a/.github/workflows/rust.yml
+++ b/.github/workflows/rust.yml
@@ -56,6 +56,7 @@ on:
     branches:
       - master
       - 0.2.x
+      - pr/890
 
 concurrency:
   group: ${{ github.workflow }}-${{ github.head_ref || github.run_id }}
diff --git a/examples/actix3_example/core/src/mutation.rs b/examples/actix3_example/core/src/mutation.rs
index 7f0150a638..dd6891d4ae 100644
--- a/examples/actix3_example/core/src/mutation.rs
+++ b/examples/actix3_example/core/src/mutation.rs
@@ -22,11 +22,11 @@ impl Mutation {
         id: i32,
         form_data: post::Model,
     ) -> Result<post::Model, DbErr> {
-        let post: post::ActiveModel = if let Ok(Some(post)) = Post::find_by_id(id).one(db).await {
-            post.into()
-        } else {
-            return Err(DbErr::Custom("Cannot find post.".to_owned()));
-        };
+        let post: post::ActiveModel = Post::find_by_id(id)
+            .one(db)
+            .await?
+            .ok_or(DbErr::Custom("Cannot find post.".to_owned()))
+            .map(Into::into)?;
 
         post::ActiveModel {
             id: post.id,
@@ -38,11 +38,11 @@ impl Mutation {
     }
 
     pub async fn delete_post(db: &DbConn, id: i32) -> Result<DeleteResult, DbErr> {
-        let post: post::ActiveModel = if let Ok(Some(post)) = Post::find_by_id(id).one(db).await {
-            post.into()
-        } else {
-            return Err(DbErr::Custom("Cannot find post.".to_owned()));
-        };
+        let post: post::ActiveModel = Post::find_by_id(id)
+            .one(db)
+            .await?
+            .ok_or(DbErr::Custom("Cannot find post.".to_owned()))
+            .map(Into::into)?;
 
         post.delete(db).await
     }
diff --git a/examples/actix_example/core/src/mutation.rs b/examples/actix_example/core/src/mutation.rs
index 7f0150a638..dd6891d4ae 100644
--- a/examples/actix_example/core/src/mutation.rs
+++ b/examples/actix_example/core/src/mutation.rs
@@ -22,11 +22,11 @@ impl Mutation {
         id: i32,
         form_data: post::Model,
     ) -> Result<post::Model, DbErr> {
-        let post: post::ActiveModel = if let Ok(Some(post)) = Post::find_by_id(id).one(db).await {
-            post.into()
-        } else {
-            return Err(DbErr::Custom("Cannot find post.".to_owned()));
-        };
+        let post: post::ActiveModel = Post::find_by_id(id)
+            .one(db)
+            .await?
+            .ok_or(DbErr::Custom("Cannot find post.".to_owned()))
+            .map(Into::into)?;
 
         post::ActiveModel {
             id: post.id,
@@ -38,11 +38,11 @@ impl Mutation {
     }
 
     pub async fn delete_post(db: &DbConn, id: i32) -> Result<DeleteResult, DbErr> {
-        let post: post::ActiveModel = if let Ok(Some(post)) = Post::find_by_id(id).one(db).await {
-            post.into()
-        } else {
-            return Err(DbErr::Custom("Cannot find post.".to_owned()));
-        };
+        let post: post::ActiveModel = Post::find_by_id(id)
+            .one(db)
+            .await?
+            .ok_or(DbErr::Custom("Cannot find post.".to_owned()))
+            .map(Into::into)?;
 
         post.delete(db).await
     }
diff --git a/examples/axum_example/core/src/mutation.rs b/examples/axum_example/core/src/mutation.rs
index 7f0150a638..dd6891d4ae 100644
--- a/examples/axum_example/core/src/mutation.rs
+++ b/examples/axum_example/core/src/mutation.rs
@@ -22,11 +22,11 @@ impl Mutation {
         id: i32,
         form_data: post::Model,
     ) -> Result<post::Model, DbErr> {
-        let post: post::ActiveModel = if let Ok(Some(post)) = Post::find_by_id(id).one(db).await {
-            post.into()
-        } else {
-            return Err(DbErr::Custom("Cannot find post.".to_owned()));
-        };
+        let post: post::ActiveModel = Post::find_by_id(id)
+            .one(db)
+            .await?
+            .ok_or(DbErr::Custom("Cannot find post.".to_owned()))
+            .map(Into::into)?;
 
         post::ActiveModel {
             id: post.id,
@@ -38,11 +38,11 @@ impl Mutation {
     }
 
     pub async fn delete_post(db: &DbConn, id: i32) -> Result<DeleteResult, DbErr> {
-        let post: post::ActiveModel = if let Ok(Some(post)) = Post::find_by_id(id).one(db).await {
-            post.into()
-        } else {
-            return Err(DbErr::Custom("Cannot find post.".to_owned()));
-        };
+        let post: post::ActiveModel = Post::find_by_id(id)
+            .one(db)
+            .await?
+            .ok_or(DbErr::Custom("Cannot find post.".to_owned()))
+            .map(Into::into)?;
 
         post.delete(db).await
     }
diff --git a/examples/graphql_example/core/src/mutation.rs b/examples/graphql_example/core/src/mutation.rs
index 6eac6814a4..1f2447fba2 100644
--- a/examples/graphql_example/core/src/mutation.rs
+++ b/examples/graphql_example/core/src/mutation.rs
@@ -23,11 +23,11 @@ impl Mutation {
         id: i32,
         form_data: note::Model,
     ) -> Result<note::Model, DbErr> {
-        let note: note::ActiveModel = if let Ok(Some(note)) = Note::find_by_id(id).one(db).await {
-            note.into()
-        } else {
-            return Err(DbErr::Custom("Cannot find note.".to_owned()));
-        };
+        let note: note::ActiveModel = Note::find_by_id(id)
+            .one(db)
+            .await?
+            .ok_or(DbErr::Custom("Cannot find note.".to_owned()))
+            .map(Into::into)?;
 
         note::ActiveModel {
             id: note.id,
@@ -39,11 +39,11 @@ impl Mutation {
     }
 
     pub async fn delete_note(db: &DbConn, id: i32) -> Result<DeleteResult, DbErr> {
-        let note: note::ActiveModel = if let Ok(Some(note)) = Note::find_by_id(id).one(db).await {
-            note.into()
-        } else {
-            return Err(DbErr::Custom("Cannot find note.".to_owned()));
-        };
+        let note: note::ActiveModel = Note::find_by_id(id)
+            .one(db)
+            .await?
+            .ok_or(DbErr::Custom("Cannot find note.".to_owned()))
+            .map(Into::into)?;
 
         note.delete(db).await
     }
diff --git a/examples/jsonrpsee_example/api/src/lib.rs b/examples/jsonrpsee_example/api/src/lib.rs
index 2e5f2c7234..f98cc18328 100644
--- a/examples/jsonrpsee_example/api/src/lib.rs
+++ b/examples/jsonrpsee_example/api/src/lib.rs
@@ -60,7 +60,7 @@ impl PostRpcServer for PpcImpl {
     async fn insert(&self, p: post::Model) -> RpcResult<i32> {
         let new_post = Mutation::create_post(&self.conn, p)
             .await
-            .expect("could not insert post");
+            .internal_call_error()?;
 
         Ok(new_post.id.unwrap())
     }
diff --git a/examples/jsonrpsee_example/core/src/mutation.rs b/examples/jsonrpsee_example/core/src/mutation.rs
index 7f0150a638..dd6891d4ae 100644
--- a/examples/jsonrpsee_example/core/src/mutation.rs
+++ b/examples/jsonrpsee_example/core/src/mutation.rs
@@ -22,11 +22,11 @@ impl Mutation {
         id: i32,
         form_data: post::Model,
     ) -> Result<post::Model, DbErr> {
-        let post: post::ActiveModel = if let Ok(Some(post)) = Post::find_by_id(id).one(db).await {
-            post.into()
-        } else {
-            return Err(DbErr::Custom("Cannot find post.".to_owned()));
-        };
+        let post: post::ActiveModel = Post::find_by_id(id)
+            .one(db)
+            .await?
+            .ok_or(DbErr::Custom("Cannot find post.".to_owned()))
+            .map(Into::into)?;
 
         post::ActiveModel {
             id: post.id,
@@ -38,11 +38,11 @@ impl Mutation {
     }
 
     pub async fn delete_post(db: &DbConn, id: i32) -> Result<DeleteResult, DbErr> {
-        let post: post::ActiveModel = if let Ok(Some(post)) = Post::find_by_id(id).one(db).await {
-            post.into()
-        } else {
-            return Err(DbErr::Custom("Cannot find post.".to_owned()));
-        };
+        let post: post::ActiveModel = Post::find_by_id(id)
+            .one(db)
+            .await?
+            .ok_or(DbErr::Custom("Cannot find post.".to_owned()))
+            .map(Into::into)?;
 
         post.delete(db).await
     }
diff --git a/examples/poem_example/core/src/mutation.rs b/examples/poem_example/core/src/mutation.rs
index 7f0150a638..dd6891d4ae 100644
--- a/examples/poem_example/core/src/mutation.rs
+++ b/examples/poem_example/core/src/mutation.rs
@@ -22,11 +22,11 @@ impl Mutation {
         id: i32,
         form_data: post::Model,
     ) -> Result<post::Model, DbErr> {
-        let post: post::ActiveModel = if let Ok(Some(post)) = Post::find_by_id(id).one(db).await {
-            post.into()
-        } else {
-            return Err(DbErr::Custom("Cannot find post.".to_owned()));
-        };
+        let post: post::ActiveModel = Post::find_by_id(id)
+            .one(db)
+            .await?
+            .ok_or(DbErr::Custom("Cannot find post.".to_owned()))
+            .map(Into::into)?;
 
         post::ActiveModel {
             id: post.id,
@@ -38,11 +38,11 @@ impl Mutation {
     }
 
     pub async fn delete_post(db: &DbConn, id: i32) -> Result<DeleteResult, DbErr> {
-        let post: post::ActiveModel = if let Ok(Some(post)) = Post::find_by_id(id).one(db).await {
-            post.into()
-        } else {
-            return Err(DbErr::Custom("Cannot find post.".to_owned()));
-        };
+        let post: post::ActiveModel = Post::find_by_id(id)
+            .one(db)
+            .await?
+            .ok_or(DbErr::Custom("Cannot find post.".to_owned()))
+            .map(Into::into)?;
 
         post.delete(db).await
     }
diff --git a/examples/rocket_example/core/src/mutation.rs b/examples/rocket_example/core/src/mutation.rs
index 7f0150a638..dd6891d4ae 100644
--- a/examples/rocket_example/core/src/mutation.rs
+++ b/examples/rocket_example/core/src/mutation.rs
@@ -22,11 +22,11 @@ impl Mutation {
         id: i32,
         form_data: post::Model,
     ) -> Result<post::Model, DbErr> {
-        let post: post::ActiveModel = if let Ok(Some(post)) = Post::find_by_id(id).one(db).await {
-            post.into()
-        } else {
-            return Err(DbErr::Custom("Cannot find post.".to_owned()));
-        };
+        let post: post::ActiveModel = Post::find_by_id(id)
+            .one(db)
+            .await?
+            .ok_or(DbErr::Custom("Cannot find post.".to_owned()))
+            .map(Into::into)?;
 
         post::ActiveModel {
             id: post.id,
@@ -38,11 +38,11 @@ impl Mutation {
     }
 
     pub async fn delete_post(db: &DbConn, id: i32) -> Result<DeleteResult, DbErr> {
-        let post: post::ActiveModel = if let Ok(Some(post)) = Post::find_by_id(id).one(db).await {
-            post.into()
-        } else {
-            return Err(DbErr::Custom("Cannot find post.".to_owned()));
-        };
+        let post: post::ActiveModel = Post::find_by_id(id)
+            .one(db)
+            .await?
+            .ok_or(DbErr::Custom("Cannot find post.".to_owned()))
+            .map(Into::into)?;
 
         post.delete(db).await
     }
diff --git a/examples/salvo_example/core/src/mutation.rs b/examples/salvo_example/core/src/mutation.rs
index 7f0150a638..dd6891d4ae 100644
--- a/examples/salvo_example/core/src/mutation.rs
+++ b/examples/salvo_example/core/src/mutation.rs
@@ -22,11 +22,11 @@ impl Mutation {
         id: i32,
         form_data: post::Model,
     ) -> Result<post::Model, DbErr> {
-        let post: post::ActiveModel = if let Ok(Some(post)) = Post::find_by_id(id).one(db).await {
-            post.into()
-        } else {
-            return Err(DbErr::Custom("Cannot find post.".to_owned()));
-        };
+        let post: post::ActiveModel = Post::find_by_id(id)
+            .one(db)
+            .await?
+            .ok_or(DbErr::Custom("Cannot find post.".to_owned()))
+            .map(Into::into)?;
 
         post::ActiveModel {
             id: post.id,
@@ -38,11 +38,11 @@ impl Mutation {
     }
 
     pub async fn delete_post(db: &DbConn, id: i32) -> Result<DeleteResult, DbErr> {
-        let post: post::ActiveModel = if let Ok(Some(post)) = Post::find_by_id(id).one(db).await {
-            post.into()
-        } else {
-            return Err(DbErr::Custom("Cannot find post.".to_owned()));
-        };
+        let post: post::ActiveModel = Post::find_by_id(id)
+            .one(db)
+            .await?
+            .ok_or(DbErr::Custom("Cannot find post.".to_owned()))
+            .map(Into::into)?;
 
         post.delete(db).await
     }
diff --git a/examples/tonic_example/core/src/mutation.rs b/examples/tonic_example/core/src/mutation.rs
index 7f0150a638..dd6891d4ae 100644
--- a/examples/tonic_example/core/src/mutation.rs
+++ b/examples/tonic_example/core/src/mutation.rs
@@ -22,11 +22,11 @@ impl Mutation {
         id: i32,
         form_data: post::Model,
     ) -> Result<post::Model, DbErr> {
-        let post: post::ActiveModel = if let Ok(Some(post)) = Post::find_by_id(id).one(db).await {
-            post.into()
-        } else {
-            return Err(DbErr::Custom("Cannot find post.".to_owned()));
-        };
+        let post: post::ActiveModel = Post::find_by_id(id)
+            .one(db)
+            .await?
+            .ok_or(DbErr::Custom("Cannot find post.".to_owned()))
+            .map(Into::into)?;
 
         post::ActiveModel {
             id: post.id,
@@ -38,11 +38,11 @@ impl Mutation {
     }
 
     pub async fn delete_post(db: &DbConn, id: i32) -> Result<DeleteResult, DbErr> {
-        let post: post::ActiveModel = if let Ok(Some(post)) = Post::find_by_id(id).one(db).await {
-            post.into()
-        } else {
-            return Err(DbErr::Custom("Cannot find post.".to_owned()));
-        };
+        let post: post::ActiveModel = Post::find_by_id(id)
+            .one(db)
+            .await?
+            .ok_or(DbErr::Custom("Cannot find post.".to_owned()))
+            .map(Into::into)?;
 
         post.delete(db).await
     }