Add latency stats to the schema_tables_with_full_table_scans view, also add an x$ counterpart

Author: MarkLeith

README.md

@@ -560,7 +560,7 @@ innodb_buffer_bytes_allocated: 311296
     innodb_buffer_rows_cached: 2
 ```
 
-#### schema_tables_with_full_table_scans
+#### schema_tables_with_full_table_scans / x$schema_tables_with_full_table_scans
 
 ##### Description
 
@@ -570,15 +570,15 @@ Finds tables that are being accessed by full table scans ordering by the number
 
 ```SQL
 mysql> select * from schema_tables_with_full_table_scans limit 5;
-+------------------+-------------------+-------------------+
-| object_schema    | object_name       | rows_full_scanned |
-+------------------+-------------------+-------------------+
-| mem              | rule_alarms       |              1210 |
-| mem30__advisors  | advisor_schedules |              1021 |
-| mem30__inventory | agent             |               498 |
-| mem              | dc_p_string       |               449 |
-| mem30__inventory | mysqlserver       |               294 |
-+------------------+-------------------+-------------------+
++--------------------+--------------------------------+-------------------+-----------+
+| object_schema      | object_name                    | rows_full_scanned | latency   |
++--------------------+--------------------------------+-------------------+-----------+
+| mem30__instruments | fsstatistics                   |          10207042 | 13.10 s   |
+| mem30__instruments | preparedstatementapidata       |            436428 | 973.27 ms |
+| mem30__instruments | mysqlprocessactivity           |            411702 | 282.07 ms |
+| mem30__instruments | querycachequeriesincachedata   |            374011 | 767.15 ms |
+| mem30__instruments | rowaccessesdata                |            322321 | 1.55 s    |
++--------------------+--------------------------------+-------------------+-----------+
 ```
 
 #### schema_unused_indexes

views/p_s/schema_tables_with_full_table_scans.sql

@@ -20,15 +20,15 @@
  * ordering by the number of rows scanned descending.
  *
  * mysql> select * from schema_tables_with_full_table_scans limit 5;
- * +------------------+-------------------+-------------------+
- * | object_schema    | object_name       | rows_full_scanned |
- * +------------------+-------------------+-------------------+
- * | mem              | rule_alarms       |              1210 |
- * | mem30__advisors  | advisor_schedules |              1021 |
- * | mem30__inventory | agent             |               498 |
- * | mem              | dc_p_string       |               449 |
- * | mem30__inventory | mysqlserver       |               294 |
- * +------------------+-------------------+-------------------+
+ * +--------------------+--------------------------------+-------------------+-----------+
+ * | object_schema      | object_name                    | rows_full_scanned | latency   |
+ * +--------------------+--------------------------------+-------------------+-----------+
+ * | mem30__instruments | fsstatistics                   |          10207042 | 13.10 s   |
+ * | mem30__instruments | preparedstatementapidata       |            436428 | 973.27 ms |
+ * | mem30__instruments | mysqlprocessactivity           |            411702 | 282.07 ms |
+ * | mem30__instruments | querycachequeriesincachedata   |            374011 | 767.15 ms |
+ * | mem30__instruments | rowaccessesdata                |            322321 | 1.55 s    |
+ * +--------------------+--------------------------------+-------------------+-----------+
  *
  */
 
@@ -39,11 +39,51 @@ CREATE OR REPLACE
 VIEW schema_tables_with_full_table_scans (
   object_schema,
   object_name,
-  rows_full_scanned
+  rows_full_scanned,
+  latency
 ) AS
 SELECT object_schema, 
        object_name,
-       count_read AS rows_full_scanned
+       count_read AS rows_full_scanned,
+       sys.format_time(sum_timer_wait) AS latency
+  FROM performance_schema.table_io_waits_summary_by_index_usage 
+ WHERE index_name IS NULL
+   AND count_read > 0
+ ORDER BY count_read DESC;
+
+/* 
+ * View: x$schema_tables_with_full_table_scans
+ *
+ * Find tables that are being accessed by full table scans
+ * ordering by the number of rows scanned descending.
+ *
+ * mysql> select * from x$schema_tables_with_full_table_scans limit 5;
+ * +--------------------+------------------------------+-------------------+----------------+
+ * | object_schema      | object_name                  | rows_full_scanned | latency        |
+ * +--------------------+------------------------------+-------------------+----------------+
+ * | mem30__instruments | fsstatistics                 |          10207042 | 13098927688488 |
+ * | mem30__instruments | preparedstatementapidata     |            436428 |   973274338980 |
+ * | mem30__instruments | mysqlprocessactivity         |            411702 |   282072434940 |
+ * | mem30__instruments | querycachequeriesincachedata |            374011 |   767152380564 |
+ * | mem30__instruments | rowaccessesdata              |            322321 |  1547594778456 |
+ * +--------------------+------------------------------+-------------------+----------------+
+ *
+ */
+
+CREATE OR REPLACE
+  ALGORITHM = MERGE
+  DEFINER = 'root'@'localhost'
+  SQL SECURITY INVOKER 
+VIEW x$schema_tables_with_full_table_scans (
+  object_schema,
+  object_name,
+  rows_full_scanned,
+  latency
+) AS
+SELECT object_schema, 
+       object_name,
+       count_read AS rows_full_scanned,
+       sum_timer_wait AS latency
   FROM performance_schema.table_io_waits_summary_by_index_usage 
  WHERE index_name IS NULL
    AND count_read > 0