diff --git a/db_schema.sql b/db_schema.sql
index a534358..3189cb7 100644
--- a/db_schema.sql
+++ b/db_schema.sql
@@ -1,3 +1,5 @@
+-- @block
+-- Create tables
 CREATE TABLE num (
     adsh      VARCHAR(255),
     tag       VARCHAR(255),
@@ -72,4 +74,15 @@ CREATE TABLE tag (
     crdr      VARCHAR(50),
     tlabel    VARCHAR(255),
     doc       TEXT
-);
\ No newline at end of file
+);
+-- @end
+
+-- @block
+-- Reset db
+SET FOREIGN_KEY_CHECKS = 0;
+DROP TABLE IF EXISTS num;
+DROP TABLE IF EXISTS pre;
+DROP TABLE IF EXISTS sub;
+DROP TABLE IF EXISTS tag;
+SET FOREIGN_KEY_CHECKS = 1;
+-- @end
\ No newline at end of file