diff --git a/src/main/resources/sql/functions/comment/comment.sql b/src/main/resources/sql/functions/comment/comment.sql
index bbd9676..a5b45b6 100644
--- a/src/main/resources/sql/functions/comment/comment.sql
+++ b/src/main/resources/sql/functions/comment/comment.sql
@@ -17,7 +17,7 @@ begin
         values (_citizen_id, _target_id, _content, _parent_id)
         returning comment_on_constitution.id into _id;
     else
-        raise exception '% no implemented', reference::text;
+        raise exception 'comment with target as "%", is no implemented', reference::text;
     end if;
 end;
 $$;
diff --git a/src/main/resources/sql/migrations/0000-init_schema.up.sql b/src/main/resources/sql/migrations/0000-init_schema.up.sql
index b082a72..d4462c3 100644
--- a/src/main/resources/sql/migrations/0000-init_schema.up.sql
+++ b/src/main/resources/sql/migrations/0000-init_schema.up.sql
@@ -167,6 +167,7 @@ $$;
 create trigger set_constitution_link_trigger
     before insert
     on article_in_title
+    for each row
 execute procedure set_constitution_link();
 
 create table article_relations
@@ -228,13 +229,41 @@ create table follow_citizen
 
 create table comment
 (
-    updated_at timestamptz default now() not null check ( updated_at >= created_at ),
-    "content"  text                      not null check ( content != '' and length(content) < 4096),
-    parent_id  uuid                      null references comment (id),
+    updated_at  timestamptz default now() not null check ( updated_at >= created_at ),
+    "content"   text                      not null check ( content != '' and length(content) < 4096),
+    parent_id   uuid                      references comment (id),
+    parents_ids uuid[],
     foreign key (citizen_id) references citizen (id),
     primary key (id)
 ) inherits (extra);
 
+create index comment_parents_ids_idx
+    on comment (parents_ids);
+
+create or replace function set_comment_parents_ids() returns trigger
+    language plpgsql as
+$$
+begin
+    if(new.parent_id is not null) then
+        new.parents_ids = (
+            select com.parents_ids || com.id
+            from "comment" com
+            where com.id = new.parent_id
+        );
+    else
+        new.parents_ids = null;
+    end if;
+
+    return new;
+end;
+$$;
+
+create trigger set_comment_parents_ids_trigger
+    before insert
+    on comment
+    for each row
+execute procedure set_comment_parents_ids();
+
 create table comment_on_article
 (
     target_reference regclass default 'article'::regclass not null,
@@ -244,6 +273,15 @@ create table comment_on_article
     primary key (id)
 ) inherits (comment);
 
+create index comment_on_article_parents_ids_idx
+    on comment_on_article (parents_ids);
+
+create trigger set_comment_on_article_parents_ids_trigger
+    before insert
+    on comment_on_article
+    for each row
+execute procedure set_comment_parents_ids();
+
 create table comment_on_constitution
 (
     target_reference regclass default 'constitution'::regclass not null,
@@ -253,6 +291,15 @@ create table comment_on_constitution
     primary key (id)
 ) inherits (comment);
 
+create index comment_on_constitution_parents_ids_idx
+    on comment_on_constitution (parents_ids);
+
+create trigger set_comment_on_constitution_parents_ids_trigger
+    before insert
+    on comment_on_constitution
+    for each row
+execute procedure set_comment_parents_ids();
+
 
 
 create table vote
diff --git a/src/test/sql/comment.sql b/src/test/sql/comment.sql
index 8cee751..8cdf552 100644
--- a/src/test/sql/comment.sql
+++ b/src/test/sql/comment.sql
@@ -26,6 +26,8 @@ declare
     }
     $json$;
     _comment_id uuid;
+    _comment_id_response uuid;
+    _comment_id_response2 uuid;
     _selected_comments json;
     _selected_comments_total int;
 begin
@@ -78,6 +80,27 @@ begin
     from find_comments_constitution_by_citizen(_citizen_id);
     assert (_selected_comments_total = 0), 'the number of comments for this citizen must be 0, "' || _selected_comments_total || '" returned';
 
+
+    select "comment"(
+        reference => 'article'::regclass,
+        target_id => (created_article->>'id')::uuid,
+        citizen_id => _citizen_id,
+        content => 'No is not exist'::text,
+        _parent_id => _comment_id::uuid
+    ) into _comment_id_response;
+
+    select "comment"(
+        reference => 'article'::regclass,
+        target_id => (created_article->>'id')::uuid,
+        citizen_id => _citizen_id,
+        content => 'No is not exist'::text,
+        _parent_id => _comment_id_response::uuid
+    ) into _comment_id_response2;
+    assert (select count(*) = 3 from "comment"), 'comment must be inserted';
+    assert (select com.parents_ids @> ARRAY[_comment_id] from "comment" com where id = _comment_id_response), 'parents_ids not contain "' || _comment_id::text || '" ' || (select com.parents_ids::text[] from "comment" com where id = _comment_id_response);
+    assert (select com.parents_ids @> ARRAY[_comment_id_response] from "comment" com where id = _comment_id_response2), 'parents_ids not contain "' || _comment_id_response::text || '" ' || (select com.parents_ids::text[] from "comment" com where id = _comment_id_response2);
+    assert (select com.parents_ids @> ARRAY[_comment_id] from "comment" com where id = _comment_id_response2), 'parents_ids not contain "' || _comment_id::text || '" ' || (select com.parents_ids::text[] from "comment" com where id = _comment_id_response2);
+
     -- delete comment and context
     delete from "comment";
     delete from article;