update migration with levenshtein length check

supabase/migrations/20240310013115_search_content_embeddings.sql

@@ -1,6 +1,5 @@
 create extension if not exists "fuzzystrmatch" with schema "extensions";
 
-
 set check_function_bodies = off;
 
 CREATE OR REPLACE FUNCTION public.get_embedding_list(query_table_name text, query_threshold integer, query_input text, query_field_name text, query_field_sub_name text, query_match_count integer)
@@ -14,22 +13,39 @@ BEGIN
         RAISE EXCEPTION 'Table % does not exist', query_table_name;
     END IF;
 
-    QUERY := format('
-        SELECT
-            embedding,
-            levenshtein($1, (content->>''%s'')::TEXT) AS levenshtein_score
-        FROM
-            %I
-        WHERE
-            levenshtein($1, (content->>''%s'')::TEXT) <= $2
-        ORDER BY
-            levenshtein_score
-        LIMIT
-            $3
-    ', query_field_name, query_table_name, query_field_name);
-
-    RETURN QUERY EXECUTE QUERY
-    USING query_input, query_threshold, query_match_count;
+    -- Check the length of query_input
+    IF LENGTH(query_input) > 255 THEN
+        -- For inputs longer than 255 characters, use exact match only
+        QUERY := format('
+            SELECT
+                embedding
+            FROM
+                %I
+            WHERE
+                (content->>''%s'')::TEXT = $1
+            LIMIT
+                $2
+        ', query_table_name, query_field_name);
+        -- Execute the query with adjusted parameters for exact match
+        RETURN QUERY EXECUTE QUERY USING query_input, query_match_count;
+    ELSE
+        -- For inputs of 255 characters or less, use Levenshtein distance
+        QUERY := format('
+            SELECT
+                embedding,
+                levenshtein($1, (content->>''%s'')::TEXT) AS levenshtein_score
+            FROM
+                %I
+            WHERE
+                levenshtein($1, (content->>''%s'')::TEXT) <= $2
+            ORDER BY
+                levenshtein_score
+            LIMIT
+                $3
+        ', query_field_name, query_table_name, query_field_name);
+        -- Execute the query with original parameters for Levenshtein distance
+        RETURN QUERY EXECUTE QUERY USING query_input, query_threshold, query_match_count;
+    END IF;
 END;
 $function$
 ;