more sql-migrations

Author: asmyasnikov

database/ydb/examples/migrations/002_add_city_to_users.down.sql

@@ -1,4 +1,3 @@
 DROP TABLE `test/cities`;
 
-ALTER TABLE `test/users`
-    DROP COLUMN city;
+ALTER TABLE `test/users` DROP COLUMN city;

database/ydb/examples/migrations/004_add_index_on_user_emails.down.sql

@@ -0,0 +1 @@
+ALTER TABLE `test/users` DROP INDEX `users_email_index`;

database/ydb/examples/migrations/004_add_index_on_user_emails.up.sql

@@ -0,0 +1 @@
+ALTER TABLE `test/users` ADD INDEX `users_email_index` GLOBAL UNIQUE ON (`email`);

database/ydb/examples/migrations/005_create_books_table.down.sql

@@ -0,0 +1 @@
+DROP TABLE `test/books`;

database/ydb/examples/migrations/005_create_books_table.up.sql

@@ -0,0 +1,6 @@
+CREATE TABLE `test/books` (
+  user_id Uint64,
+  name    Text,
+  author  Text,
+  PRIMARY KEY (user_id)
+);

database/ydb/examples/migrations/006_create_movies_table.down.sql

@@ -0,0 +1 @@
+DROP TABLE `test/movies`;

database/ydb/examples/migrations/006_create_movies_table.up.sql

@@ -0,0 +1,6 @@
+CREATE TABLE `test/movies` (
+  user_id   Uint64,
+  name      Text,
+  director  Text,
+  PRIMARY KEY (user_id)
+);