diff --git a/schema.sql b/schema.sql
index 413ae5c..4e4d3c7 100644
--- a/schema.sql
+++ b/schema.sql
@@ -5,7 +5,7 @@ USE emojis;
 
 CREATE TABLE IF NOT EXISTS emoji_clicks (
     id INT PRIMARY KEY AUTO_INCREMENT,
-    user_anon_data TEXT NOT NULL,
+    user_anon_data VARCHAR(50) UNIQUE,
     post_id TEXT NOT NULL,
     emoji TEXT NOT NULL,
     created_at DATETIME DEFAULT CURRENT_TIMESTAMP