diff --git a/app/corpora/background_functions.py b/app/corpora/background_functions.py
index e12cf51c..442b9424 100644
--- a/app/corpora/background_functions.py
+++ b/app/corpora/background_functions.py
@@ -3,7 +3,7 @@ from app.models import Corpus, CorpusFile
 
 def delete_corpus_(app, corpus_id):
     with app.app_context():
-        corpus = Corpus.query.filter_by(id=corpus_id).first()
+        corpus = Corpus.query.get(corpus_id)
         if corpus is None:
             raise Exception('Corpus {} not found!'.format(corpus_id))
         corpus.delete()
@@ -11,7 +11,7 @@ def delete_corpus_(app, corpus_id):
 
 def delete_corpus_file_(app, corpus_file_id):
     with app.app_context():
-        corpus_file = CorpusFile.query.filter_by(id=corpus_file_id).first()
+        corpus_file = CorpusFile.query.get(corpus_file_id)
         if corpus_file is None:
             raise Exception('Corpus file {} not found!'.format(corpus_file_id))
         corpus_file.delete()
@@ -19,7 +19,7 @@ def delete_corpus_file_(app, corpus_file_id):
 
 def edit_corpus_file_(app, corpus_file_id):
     with app.app_context():
-        corpus_file = CorpusFile.query.filter_by(id=corpus_file_id).first()
+        corpus_file = CorpusFile.query.get(corpus_file_id)
         if corpus_file is None:
             raise Exception('Corpus file {} not found!'.format(corpus_file_id))
         corpus_file.insert_metadata()
diff --git a/app/corpora/events.py b/app/corpora/events.py
index 81c184c9..c25aadbe 100644
--- a/app/corpora/events.py
+++ b/app/corpora/events.py
@@ -22,7 +22,7 @@ analysis_clients = {}
 @socketio.on('init_corpus_analysis')
 @login_required
 def init_corpus_analysis(corpus_id):
-    corpus = Corpus.query.filter_by(id=corpus_id).first()
+    corpus = Corpus.query.get(corpus_id)
     if corpus is None:
         socketio.emit('init_corpus_analysis', '[ERROR 404]: Not Found',
                       room=request.sid)
@@ -85,7 +85,10 @@ def recv_query(message):
 
 def observe_corpus_analysis_connection(app, corpus_id, session_id):
     with app.app_context():
-        corpus = Corpus.query.filter_by(id=corpus_id).first()
+        corpus = Corpus.query.get(corpus_id)
+        if corpus is None:
+            ''' TODO: Handle this '''
+            return
         while corpus.status != 'analysing':
             db.session.refresh(corpus)
             socketio.sleep(3)
diff --git a/app/events.py b/app/events.py
index 73022cc5..c05ea980 100644
--- a/app/events.py
+++ b/app/events.py
@@ -72,7 +72,10 @@ def user_ressource_subscription_handler(app, user_id, session_id,
                      else 'update-jobs'}
     with app.app_context():
         # Gather current values from database.
-        user = User.query.filter_by(id=user_id).first()
+        user = User.query.get(user_id)
+        if user is None:
+            ''' TODO: Handle this '''
+            return
         corpora = {corpus.id: corpus.to_dict() for corpus in user.corpora}
         jobs = {job.id: job.to_dict() for job in user.jobs}
         # Send initial values to the user.
diff --git a/app/jobs/background_functions.py b/app/jobs/background_functions.py
index db47332e..f90c2daa 100644
--- a/app/jobs/background_functions.py
+++ b/app/jobs/background_functions.py
@@ -3,7 +3,7 @@ from app.models import Job
 
 def delete_job_(app, job_id):
     with app.app_context():
-        job = Job.query.filter_by(id=job_id).first()
+        job = Job.query.get(job_id)
         if job is None:
             raise Exception('Job {} not found!'.format(job_id))
         job.delete()
diff --git a/app/profile/background_functions.py b/app/profile/background_functions.py
index db136f72..62be9b6f 100644
--- a/app/profile/background_functions.py
+++ b/app/profile/background_functions.py
@@ -3,7 +3,7 @@ from app.models import User
 
 def delete_user_(app, user_id):
     with app.app_context():
-        user = User.query.filter_by(id=user_id).first()
+        user = User.query.get(user_id)
         if user is None:
             raise Exception('User {} not found!'.format(user_id))
         user.delete()