-- Copyright (c) 2014, 2021, Oracle and/or its affiliates.
--
-- This program is free software; you can redistribute it and/or modify
-- it under the terms of the GNU General Public License, version 2.0,
-- as published by the Free Software Foundation.
--
-- This program is also distributed with certain software (including
-- but not limited to OpenSSL) that is licensed under separate terms,
-- as designated in a particular file or component or in included license
-- documentation.  The authors of MySQL hereby grant you an additional
-- permission to link the program and your derivative works with the
-- separately licensed software that they have included with MySQL.
--
-- This program is distributed in the hope that it will be useful,
-- but WITHOUT ANY WARRANTY; without even the implied warranty of
-- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-- GNU General Public License, version 2.0, for more details.
--
-- You should have received a copy of the GNU General Public License
-- along with this program; if not, write to the Free Software
-- Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA

--
-- View: x$innodb_buffer_stats_by_schema
-- 
-- Summarizes the output of the INFORMATION_SCHEMA.INNODB_BUFFER_PAGE 
-- table, aggregating by schema
--
-- mysql> select * from x$innodb_buffer_stats_by_schema;
-- +--------------------------+-----------+--------+-------+--------------+-----------+-------------+
-- | object_schema            | allocated | data   | pages | pages_hashed | pages_old | rows_cached |
-- +--------------------------+-----------+--------+-------+--------------+-----------+-------------+
-- | mem30_trunk__instruments |   1769472 | 522272 |   108 |          108 |       108 |        3885 |
-- | InnoDB System            |    704512 | 360054 |    43 |           43 |        43 |         862 |
-- | mem30_trunk__events      |     81920 |  22125 |     5 |            5 |         5 |         229 |
-- +--------------------------+-----------+--------+-------+--------------+-----------+-------------+
--

CREATE OR REPLACE
  ALGORITHM = TEMPTABLE
  DEFINER = 'mysql.sys'@'localhost'
  SQL SECURITY INVOKER 
VIEW x$innodb_buffer_stats_by_schema (
  object_schema,
  allocated,
  data,
  pages,
  pages_hashed,
  pages_old,
  rows_cached
) AS
SELECT IF(LOCATE('.', ibp.table_name) = 0, 'InnoDB System', REPLACE(SUBSTRING_INDEX(ibp.table_name, '.', 1), '`', '')) AS object_schema,
       SUM(IF(ibp.compressed_size = 0, 16384, compressed_size)) AS allocated,
       SUM(ibp.data_size) AS data,
       COUNT(ibp.page_number) AS pages,
       COUNT(IF(ibp.is_hashed = 'YES', 1, NULL)) AS pages_hashed,
       COUNT(IF(ibp.is_old = 'YES', 1, NULL)) AS pages_old,
       ROUND(IFNULL(SUM(ibp.number_records)/NULLIF(COUNT(DISTINCT ibp.index_name), 0), 0)) AS rows_cached 
  FROM information_schema.innodb_buffer_page ibp 
 WHERE table_name IS NOT NULL
 GROUP BY object_schema
 ORDER BY SUM(IF(ibp.compressed_size = 0, 16384, compressed_size)) DESC;
