diff --git a/src/controllers/notifications_controller.rs b/src/controllers/notifications_controller.rs
index b020825..d61d0f0 100644
--- a/src/controllers/notifications_controller.rs
+++ b/src/controllers/notifications_controller.rs
@@ -6,9 +6,28 @@ use crate::api_data::notification_api::NotificationAPI;
 use crate::api_data::res_count_all_unreads::ResCountAllUnread;
 use crate::api_data::res_number_unread_notifications::ResNumberUnreadNotifications;
 use crate::controllers::routes::RequestResult;
+use crate::data::error::ResultBoxError;
 use crate::data::http_request_handler::HttpRequestHandler;
+use crate::data::notification::PartialNotification;
 use crate::helpers::{conversations_helper, friends_helper, notifications_helper};
 
+impl HttpRequestHandler {
+    /// Get the id of a notification included in the request
+    pub fn post_notif_id(&mut self, name: &str) -> ResultBoxError<u64> {
+        let notif_id = self.post_u64(name)?;
+
+        let notif = PartialNotification::new()
+            .set_id(notif_id)
+            .set_dest_user_id(self.user_id_ref()?);
+
+        if !notifications_helper::similar_exists(&notif)? {
+            self.not_found("Specified notification not found!".to_string())?;
+        }
+
+        Ok(notif_id)
+    }
+}
+
 /// Count the number of unread notifications
 pub fn count_unread(r: &mut HttpRequestHandler) -> RequestResult {
     let number = notifications_helper::count_unread(r.user_id_ref()?)?;
@@ -32,4 +51,13 @@ pub fn get_list_unread(r: &mut HttpRequestHandler) -> RequestResult {
     let list = notifications_helper::get_list_unread(r.user_id_ref()?)?;
 
     r.set_response(NotificationAPI::for_list(&list))
+}
+
+/// Mark a notification as seen
+pub fn mark_seen(r: &mut HttpRequestHandler) -> RequestResult {
+    let notif_id = r.post_notif_id("notifID")?;
+    let delete_similar = r.post_bool_opt("delete_similar", false);
+
+    // TODO : continue implementation
+    r.success("continue implementation")
 }
\ No newline at end of file
diff --git a/src/controllers/routes.rs b/src/controllers/routes.rs
index 3123acb..5586239 100644
--- a/src/controllers/routes.rs
+++ b/src/controllers/routes.rs
@@ -251,6 +251,8 @@ pub fn get_routes() -> Vec<Route> {
 
         Route::post("/notifications/get_list_unread", Box::new(notifications_controller::get_list_unread)),
 
+        Route::post("/notifications/mark_seen", Box::new(notifications_controller::mark_seen)),
+
 
         // Movies controller
         Route::post("/movies/get_list", Box::new(movies_controller::get_list)),
diff --git a/src/data/notification.rs b/src/data/notification.rs
index 97c615f..1c8064a 100644
--- a/src/data/notification.rs
+++ b/src/data/notification.rs
@@ -151,4 +151,46 @@ pub struct Notification {
     pub visibility: NotifEventVisibility,
     pub container_id: Option<u64>,
     pub container_type: Option<NotifElemType>,
+}
+
+pub struct PartialNotification {
+    pub id: Option<u64>,
+    pub time_create: Option<u64>,
+    pub seen: Option<bool>,
+    pub from_user_id: Option<UserID>,
+    pub dest_user_id: Option<UserID>,
+    pub on_elem_id: Option<u64>,
+    pub on_elem_type: Option<NotifElemType>,
+    pub kind: Option<NotifEventType>,
+    pub visibility: Option<NotifEventVisibility>,
+    pub container_id: Option<u64>,
+    pub container_type: Option<NotifElemType>,
+}
+
+impl PartialNotification {
+    pub fn new() -> PartialNotification {
+        PartialNotification {
+            id: None,
+            time_create: None,
+            seen: None,
+            from_user_id: None,
+            dest_user_id: None,
+            on_elem_id: None,
+            on_elem_type: None,
+            kind: None,
+            visibility: None,
+            container_id: None,
+            container_type: None,
+        }
+    }
+
+    pub fn set_id(mut self, id: u64) -> PartialNotification {
+        self.id = Some(id);
+        self
+    }
+
+    pub fn set_dest_user_id(mut self, id: &UserID) -> PartialNotification {
+        self.dest_user_id = Some(id.clone());
+        self
+    }
 }
\ No newline at end of file
diff --git a/src/helpers/database.rs b/src/helpers/database.rs
index 02e5eb5..3d1be84 100644
--- a/src/helpers/database.rs
+++ b/src/helpers/database.rs
@@ -75,7 +75,7 @@ pub struct QueryInfo {
     joins: Vec<QueryJoin>,
 
     /// Query limits
-    pub conditions: collections::HashMap<String, String>,
+    pub conditions: collections::HashMap<String, mysql::Value>,
 
     /// Custom WHERE condition
     pub custom_where: Option<String>,
@@ -137,43 +137,50 @@ impl QueryInfo {
         self
     }
 
+    pub fn add_conditions(mut self, map: &HashMap<String, mysql::Value>) -> QueryInfo {
+        for (k,v) in map {
+            self.conditions.insert(k.to_string(), v.clone());
+        }
+        self
+    }
+
     pub fn cond(mut self, key: &str, val: &str) -> QueryInfo {
-        self.conditions.insert(key.to_string(), val.to_string());
+        self.conditions.insert(key.to_string(), mysql::Value::from(val));
         self
     }
 
     pub fn cond_u32(mut self, key: &str, val: u32) -> QueryInfo {
-        self.conditions.insert(key.to_string(), val.to_string());
+        self.conditions.insert(key.to_string(), mysql::Value::from(val));
         self
     }
 
     pub fn cond_u64(mut self, key: &str, val: u64) -> QueryInfo {
-        self.conditions.insert(key.to_string(), val.to_string());
+        self.conditions.insert(key.to_string(), mysql::Value::from(val));
         self
     }
 
     pub fn cond_i64(mut self, key: &str, val: i64) -> QueryInfo {
-        self.conditions.insert(key.to_string(), val.to_string());
+        self.conditions.insert(key.to_string(), mysql::Value::from(val));
         self
     }
 
     pub fn cond_user_id(mut self, key: &str, val: &UserID) -> QueryInfo {
-        self.conditions.insert(key.to_string(), val.id().to_string());
+        self.conditions.insert(key.to_string(), mysql::Value::from(val.id()));
         self
     }
 
     pub fn cond_group_id(mut self, key: &str, val: &GroupID) -> QueryInfo {
-        self.conditions.insert(key.to_string(), val.id().to_string());
+        self.conditions.insert(key.to_string(), mysql::Value::from(val.id()));
         self
     }
 
     pub fn cond_legacy_bool(mut self, key: &str, val: bool) -> QueryInfo {
         let val = match val {
-            true => "1".to_string(),
-            false => "0".to_string()
+            true => 1,
+            false => 0
         };
 
-        self.conditions.insert(key.to_string(), val);
+        self.conditions.insert(key.to_string(), mysql::Value::from(val));
         self
     }
 
@@ -451,7 +458,7 @@ pub fn query<E, F: Fn(&RowResult) -> ProcessRowResult<E>>(info: QueryInfo, proce
 
         for (k, v) in &info.conditions {
             where_args.push(format!("{} = ?", k));
-            params.push(mysql::Value::from(v));
+            params.push(v.clone());
         }
 
         let where_args = format!(" WHERE {} ", where_args.join(" AND "));
diff --git a/src/helpers/notifications_helper.rs b/src/helpers/notifications_helper.rs
index 936a66b..8842b0d 100644
--- a/src/helpers/notifications_helper.rs
+++ b/src/helpers/notifications_helper.rs
@@ -2,12 +2,22 @@
 //!
 //! @author Pierre Hubert
 
+use std::collections::HashMap;
+
 use crate::constants::database_tables_names::NOTIFICATIONS_TABLE;
 use crate::data::error::ResultBoxError;
-use crate::data::notification::{NotifElemType, NotifEventType, NotifEventVisibility, Notification};
+use crate::data::notification::{NotifElemType, NotifEventType, NotifEventVisibility, Notification, PartialNotification};
 use crate::data::user::UserID;
 use crate::helpers::database;
 
+/// check out whether a similar notification exists for given specifications
+pub fn similar_exists(n: &PartialNotification) -> ResultBoxError<bool> {
+    database::QueryInfo::new(NOTIFICATIONS_TABLE)
+        .add_conditions(&notif_to_db(n, false))
+        .exec_count()
+        .map(|f| f > 0)
+}
+
 /// Count the number of unread notifications
 pub fn count_unread(user_id: &UserID) -> ResultBoxError<u64> {
     database::QueryInfo::new(NOTIFICATIONS_TABLE)
@@ -42,4 +52,62 @@ fn db_to_notif(row: &database::RowResult) -> ResultBoxError<Notification> {
         container_type: row.get_optional_str("from_container_type")?
             .map(|s| NotifElemType::from_db(&s)),
     })
+}
+
+/// Turn a notification into a database entry
+fn notif_to_db(n: &PartialNotification, complete_information: bool) -> HashMap<String, mysql::Value> {
+    let mut map = HashMap::new();
+
+    if let Some(id) = n.id {
+        map.insert("id".to_string(), mysql::Value::UInt(id));
+    }
+
+    if let Some(seen) = n.seen {
+        map.insert("seen".to_string(), mysql::Value::Int(match seen {
+            true => 1,
+            false => 0,
+        }));
+    }
+
+    if let Some(from_user_id) = &n.from_user_id {
+        map.insert("from_user_id".to_string(), mysql::Value::UInt(from_user_id.id()));
+    }
+
+    if let Some(dest_user_id) = &n.dest_user_id {
+        map.insert("dest_user_id".to_string(), mysql::Value::UInt(dest_user_id.id()));
+    }
+
+    if let Some(kind) = &n.kind {
+        map.insert("type".to_string(), mysql::Value::from(kind.to_db()));
+    }
+
+    if let Some(on_elem_id) = n.on_elem_id {
+        map.insert("on_elem_id".to_string(), mysql::Value::from(on_elem_id));
+    }
+
+    if let Some(on_elem_type) = &n.on_elem_type {
+        map.insert("on_elem_type".to_string(), mysql::Value::from(on_elem_type.to_db()));
+    }
+
+
+    if complete_information {
+        if let Some(from_container_id) = n.container_id {
+            map.insert("from_container_id".to_string(), mysql::Value::from(from_container_id));
+        }
+
+        if let Some(from_container_type) = &n.container_type {
+            map.insert("from_container_type".to_string(), mysql::Value::from(from_container_type.to_db()));
+        }
+
+        if let Some(time_create) = n.time_create {
+            map.insert("time_create".to_string(), mysql::Value::from(time_create));
+        }
+
+        if let Some(visibility) = &n.visibility {
+            map.insert("visibility".to_string(), mysql::Value::from(visibility.to_db()));
+        }
+    }
+
+
+    map
 }
\ No newline at end of file