diff --git a/nomen/main.py b/nomen/main.py
index 2b8db78..fe33fbf 100644
--- a/nomen/main.py
+++ b/nomen/main.py
@@ -79,7 +79,11 @@ class Nomen(Bot):
         return prefix
 
     async def set_guild_prefix(self, guild: Guild, prefix):
-        await self.db.execute("UPDATE guilds SET prefix = ? WHERE guild_id=?", (prefix, guild.id))
+        await self.db.execute(
+            "INSERT INTO guilds VALUES(:guild_id, :prefix) ON CONFLICT(guild_id) DO UPDATE SET prefix = :prefix",
+            {"guild_id": guild.id, "prefix": prefix},
+        )
+        await self.db.commit()
         self.prefixes[guild.id] = prefix
 
     async def start(self, *args, **kwargs):