Document box.info.schema_version (#3505)

Author: andreyaksenov

doc/reference/reference_lua/box_info.rst

@@ -102,6 +102,9 @@ Below is a list of all ``box.info`` functions and members.
         *  - :doc:`./box_info/ro_reason`
            - Show the current mode of an instance (writable or read-only)
 
+        *  - :doc:`./box_info/schema_version`
+           - Show the database schema version
+
 ..  toctree::
     :hidden:
 
@@ -114,3 +117,4 @@ Below is a list of all ``box.info`` functions and members.
     box_info/election
     box_info/synchro
     box_info/ro_reason
+    box_info/schema_version

doc/reference/reference_lua/box_info/schema_version.rst

@@ -0,0 +1,25 @@
+..  _box_info_schema_version:
+
+================================================================================
+box.info.schema_version
+================================================================================
+
+..  module:: box.info
+
+..  data:: schema_version
+
+    Since :doc:`2.11.0 </release/2.11.0>`.
+    Show the database schema version.
+    A schema version is a number that indicates whether the :ref:`database schema <index-box-data_schema_description>` is changed.
+    For example, the ``schema_version`` value grows if a :ref:`space <index-box_space>` or :ref:`index <index-box_index>` is added or deleted, or a space, index, or field name is changed.
+
+    :rtype: number
+
+    **Example:**
+
+    ..  code-block:: tarantoolsession
+
+        tarantool> box.info.schema_version
+        ---
+        - 84
+        ...