update tags add function

migrations/0_init_schema.sql

@@ -8,7 +8,7 @@ CREATE TABLE IF NOT EXISTS questions (
 -- Create tags table
 CREATE TABLE IF NOT EXISTS tags (
     id SERIAL PRIMARY KEY,
-    label TEXT NOT NULL
+    label TEXT UNIQUE NOT NULL
 );
 
 -- Create question_tag table

src/pg_store.rs

@@ -72,13 +72,14 @@ impl Store {
         }
     }
 
+    // Add new tags to tags table, only if tags with existing label do not exist
     pub async fn _add_tags(&mut self, tag_labels: Vec<String>) -> Result<Vec<Tag>, String> {
         let insert_values: Vec<String> = tag_labels
             .iter()
             .map(|label| format!("({}),", label))
             .collect();
-
-        let result = sqlx::query("INSERT INTO tags (label) VALUES $1 RETURNING id, label")
+        let query = "INSERT INTO tags (label) VALUES $1 ON CONFLICT (label) DO NOTHING RETURNING *"
+        let result = sqlx::query(query)
             .bind(insert_values)
             .fetch_all(&self.connection)
             .await;
@@ -190,13 +191,6 @@ impl Store {
         }
     }
 
-    /// Creates passed in tag labels in the tags table, only if they do not already exists
-    /// Returns list of all tags from passed in labels, regardless of if they already existed
-    pub fn _add_tags_if_not_exists(&mut self, _tags_labels: Vec<String>) {
-        todo!()
-    }
-
-    ///
     pub fn _sync_question_tags(&mut self, _tags: Vec<Tag>) {
         todo!()
     }