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mariadb/mysql-test/main/information_schema_all_engines.result
Monty b66cdbd1ea Changing all cost calculation to be given in milliseconds 
This makes it easier to compare different costs and also allows
the optimizer to optimizer different storage engines more reliably.

- Added tests/check_costs.pl, a tool to verify optimizer cost calculations.
  - Most engine costs has been found with this program. All steps to
    calculate the new costs are documented in Docs/optimizer_costs.txt

- User optimizer_cost variables are given in microseconds (as individual
  costs can be very small). Internally they are stored in ms.
- Changed DISK_READ_COST (was DISK_SEEK_BASE_COST) from a hard disk cost
  (9 ms) to common SSD cost (400MB/sec).
- Removed cost calculations for hard disks (rotation etc).
- Changed the following handler functions to return IO_AND_CPU_COST.
  This makes it easy to apply different cost modifiers in ha_..time()
  functions for io and cpu costs.
  - scan_time()
  - rnd_pos_time() & rnd_pos_call_time()
  - keyread_time()
- Enhanched keyread_time() to calculate the full cost of reading of a set
  of keys with a given number of ranges and optional number of blocks that
  need to be accessed.
- Removed read_time() as keyread_time() + rnd_pos_time() can do the same
  thing and more.
- Tuned cost for: heap, myisam, Aria, InnoDB, archive and MyRocks.
  Used heap table costs for json_table. The rest are using default engine
  costs.
- Added the following new optimizer variables:
  - optimizer_disk_read_ratio
  - optimizer_disk_read_cost
  - optimizer_key_lookup_cost
  - optimizer_row_lookup_cost
  - optimizer_row_next_find_cost
  - optimizer_scan_cost
- Moved all engine specific cost to OPTIMIZER_COSTS structure.
- Changed costs to use 'records_out' instead of 'records_read' when
  recalculating costs.
- Split optimizer_costs.h to optimizer_costs.h and optimizer_defaults.h.
  This allows one to change costs without having to compile a lot of
  files.
- Updated costs for filter lookup.
- Use a better cost estimate in best_extension_by_limited_search()
  for the sorting cost.
- Fixed previous issues with 'filtered' explain column as we are now
  using 'records_out' (min rows seen for table) to calculate filtering.
  This greatly simplifies the filtering code in
  JOIN_TAB::save_explain_data().

This change caused a lot of queries to be optimized differently than
before, which exposed different issues in the optimizer that needs to
be fixed.  These fixes are in the following commits.  To not have to
change the same test case over and over again, the changes in the test
cases are done in a single commit after all the critical change sets
are done.

InnoDB changes:
- Updated InnoDB to not divide big range cost with 2.
- Added cost for InnoDB (innobase_update_optimizer_costs()).
- Don't mark clustered primary key with HA_KEYREAD_ONLY. This will
  prevent that the optimizer is trying to use index-only scans on
  the clustered key.
- Disabled ha_innobase::scan_time() and ha_innobase::read_time() and
  ha_innobase::rnd_pos_time() as the default engine cost functions now
  works good for InnoDB.

Other things:
- Added  --show-query-costs (\Q) option to mysql.cc to show the query
  cost after each query (good when working with query costs).
- Extended my_getopt with GET_ADJUSTED_VALUE which allows one to adjust
  the value that user is given. This is used to change cost from
  microseconds (user input) to milliseconds (what the server is
  internally using).
- Added include/my_tracker.h  ; Useful include file to quickly test
  costs of a function.
- Use handler::set_table() in all places instead of 'table= arg'.
- Added SHOW_OPTIMIZER_COSTS to sys variables. These are input and
  shown in microseconds for the user but stored as milliseconds.
  This is to make the numbers easier to read for the user (less
  pre-zeros).  Implemented in 'Sys_var_optimizer_cost' class.
- In test_quick_select() do not use index scans if 'no_keyread' is set
  for the table. This is what we do in other places of the server.
- Added THD parameter to Unique::get_use_cost() and
  check_index_intersect_extension() and similar functions to be able
  to provide costs to called functions.
- Changed 'records' to 'rows' in optimizer_trace.
- Write more information to optimizer_trace.
- Added INDEX_BLOCK_FILL_FACTOR_MUL (4) and INDEX_BLOCK_FILL_FACTOR_DIV (3)
  to calculate usage space of keys in b-trees. (Before we used numeric
  constants).
- Removed code that assumed that b-trees has similar costs as binary
  trees. Replaced with engine calls that returns the cost.
- Added Bitmap::find_first_bit()
- Added timings to join_cache for ANALYZE table (patch by Sergei Petrunia).
- Added records_init and records_after_filter to POSITION to remember
  more of what best_access_patch() calculates.
- table_after_join_selectivity() changed to recalculate 'records_out'
  based on the new fields from best_access_patch()

Bug fixes:
- Some queries did not update last_query_cost (was 0). Fixed by moving
  setting thd->...last_query_cost in JOIN::optimize().
- Write '0' as number of rows for const tables with a matching row.

Some internals:
- Engine cost are stored in OPTIMIZER_COSTS structure.  When a
  handlerton is created, we also created a new cost variable for the
  handlerton. We also create a new variable if the user changes a
  optimizer cost for a not yet loaded handlerton either with command
  line arguments or with SET
  @@global.engine.optimizer_cost_variable=xx.
- There are 3 global OPTIMIZER_COSTS variables:
  default_optimizer_costs   The default costs + changes from the
                            command line without an engine specifier.
  heap_optimizer_costs      Heap table costs, used for temporary tables
  tmp_table_optimizer_costs The cost for the default on disk internal
                            temporary table (MyISAM or Aria)
- The engine cost for a table is stored in table_share. To speed up
  accesses the handler has a pointer to this. The cost is copied
  to the table on first access. If one wants to change the cost one
  must first update the global engine cost and then do a FLUSH TABLES.
  This was done to be able to access the costs for an open table
  without any locks.
- When a handlerton is created, the cost are updated the following way:
  See sql/keycaches.cc for details:
  - Use 'default_optimizer_costs' as a base
  - Call hton->update_optimizer_costs() to override with the engines
    default costs.
  - Override the costs that the user has specified for the engine.
  - One handler open, copy the engine cost from handlerton to TABLE_SHARE.
  - Call handler::update_optimizer_costs() to allow the engine to update
    cost for this particular table.
  - There are two costs stored in THD. These are copied to the handler
    when the table is used in a query:
    - optimizer_where_cost
    - optimizer_scan_setup_cost
- Simply code in best_access_path() by storing all cost result in a
  structure. (Idea/Suggestion by Igor)
2023-02-02 23:54:45 +03:00

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use INFORMATION_SCHEMA;
show tables;
Tables_in_information_schema
ALL_PLUGINS
APPLICABLE_ROLES
CHARACTER_SETS
CHECK_CONSTRAINTS
CLIENT_STATISTICS
COLLATIONS
COLLATION_CHARACTER_SET_APPLICABILITY
COLUMNS
COLUMN_PRIVILEGES
ENABLED_ROLES
ENGINES
EVENTS
FILES
GEOMETRY_COLUMNS
GLOBAL_STATUS
GLOBAL_VARIABLES
INDEX_STATISTICS
INNODB_BUFFER_PAGE
INNODB_BUFFER_PAGE_LRU
INNODB_BUFFER_POOL_STATS
INNODB_CMP
INNODB_CMPMEM
INNODB_CMPMEM_RESET
INNODB_CMP_PER_INDEX
INNODB_CMP_RESET
INNODB_LOCKS
INNODB_LOCK_WAITS
INNODB_METRICS
INNODB_SYS_COLUMNS
INNODB_SYS_FIELDS
INNODB_SYS_FOREIGN
INNODB_SYS_FOREIGN_COLS
INNODB_SYS_INDEXES
INNODB_SYS_TABLES
INNODB_SYS_TABLESTATS
INNODB_SYS_VIRTUAL
INNODB_TABLESPACES_ENCRYPTION
INNODB_TRX
KEYWORDS
KEY_CACHES
KEY_COLUMN_USAGE
OPTIMIZER_COSTS
OPTIMIZER_TRACE
PARAMETERS
PARTITIONS
PLUGINS
PROCESSLIST
PROFILING
REFERENTIAL_CONSTRAINTS
ROUTINES
SCHEMATA
SCHEMA_PRIVILEGES
SESSION_STATUS
SESSION_VARIABLES
SPATIAL_REF_SYS
SQL_FUNCTIONS
STATISTICS
SYSTEM_VARIABLES
TABLES
TABLESPACES
TABLE_CONSTRAINTS
TABLE_PRIVILEGES
TABLE_STATISTICS
TRIGGERS
USER_PRIVILEGES
USER_STATISTICS
VIEWS
SELECT t.table_name, c1.column_name
FROM information_schema.tables t
INNER JOIN
information_schema.columns c1
ON t.table_schema = c1.table_schema AND
t.table_name = c1.table_name
WHERE t.table_schema = 'information_schema' AND
c1.ordinal_position =
( SELECT COALESCE(MIN(c2.ordinal_position),1)
FROM information_schema.columns c2
WHERE c2.table_schema = t.table_schema AND
c2.table_name = t.table_name AND
c2.column_name LIKE '%SCHEMA%'
) order by t.table_name;
table_name column_name
ALL_PLUGINS PLUGIN_NAME
APPLICABLE_ROLES GRANTEE
CHARACTER_SETS CHARACTER_SET_NAME
CHECK_CONSTRAINTS CONSTRAINT_SCHEMA
CLIENT_STATISTICS CLIENT
COLLATIONS COLLATION_NAME
COLLATION_CHARACTER_SET_APPLICABILITY COLLATION_NAME
COLUMNS TABLE_SCHEMA
COLUMN_PRIVILEGES TABLE_SCHEMA
ENABLED_ROLES ROLE_NAME
ENGINES ENGINE
EVENTS EVENT_SCHEMA
FILES TABLE_SCHEMA
GEOMETRY_COLUMNS F_TABLE_SCHEMA
GLOBAL_STATUS VARIABLE_NAME
GLOBAL_VARIABLES VARIABLE_NAME
INDEX_STATISTICS TABLE_SCHEMA
INNODB_BUFFER_PAGE POOL_ID
INNODB_BUFFER_PAGE_LRU POOL_ID
INNODB_BUFFER_POOL_STATS POOL_ID
INNODB_CMP page_size
INNODB_CMPMEM page_size
INNODB_CMPMEM_RESET page_size
INNODB_CMP_PER_INDEX database_name
INNODB_CMP_RESET page_size
INNODB_LOCKS lock_id
INNODB_LOCK_WAITS requesting_trx_id
INNODB_METRICS NAME
INNODB_SYS_COLUMNS TABLE_ID
INNODB_SYS_FIELDS INDEX_ID
INNODB_SYS_FOREIGN ID
INNODB_SYS_FOREIGN_COLS ID
INNODB_SYS_INDEXES INDEX_ID
INNODB_SYS_TABLES TABLE_ID
INNODB_SYS_TABLESTATS TABLE_ID
INNODB_SYS_VIRTUAL TABLE_ID
INNODB_TABLESPACES_ENCRYPTION SPACE
INNODB_TRX trx_id
KEYWORDS WORD
KEY_CACHES KEY_CACHE_NAME
KEY_COLUMN_USAGE CONSTRAINT_SCHEMA
OPTIMIZER_COSTS ENGINE
OPTIMIZER_TRACE QUERY
PARAMETERS SPECIFIC_SCHEMA
PARTITIONS TABLE_SCHEMA
PLUGINS PLUGIN_NAME
PROCESSLIST ID
PROFILING QUERY_ID
REFERENTIAL_CONSTRAINTS CONSTRAINT_SCHEMA
ROUTINES ROUTINE_SCHEMA
SCHEMATA SCHEMA_NAME
SCHEMA_PRIVILEGES TABLE_SCHEMA
SESSION_STATUS VARIABLE_NAME
SESSION_VARIABLES VARIABLE_NAME
SPATIAL_REF_SYS SRID
SQL_FUNCTIONS FUNCTION
STATISTICS TABLE_SCHEMA
SYSTEM_VARIABLES VARIABLE_NAME
TABLES TABLE_SCHEMA
TABLESPACES TABLESPACE_NAME
TABLE_CONSTRAINTS CONSTRAINT_SCHEMA
TABLE_PRIVILEGES TABLE_SCHEMA
TABLE_STATISTICS TABLE_SCHEMA
TRIGGERS TRIGGER_SCHEMA
USER_PRIVILEGES GRANTEE
USER_STATISTICS USER
VIEWS TABLE_SCHEMA
SELECT t.table_name, c1.column_name
FROM information_schema.tables t
INNER JOIN
information_schema.columns c1
ON t.table_schema = c1.table_schema AND
t.table_name = c1.table_name
WHERE t.table_schema = 'information_schema' AND
c1.ordinal_position =
( SELECT COALESCE(MIN(c2.ordinal_position),1)
FROM information_schema.columns c2
WHERE c2.table_schema = 'information_schema' AND
c2.table_name = t.table_name AND
c2.column_name LIKE '%SCHEMA%'
) order by t.table_name;
table_name column_name
ALL_PLUGINS PLUGIN_NAME
APPLICABLE_ROLES GRANTEE
CHARACTER_SETS CHARACTER_SET_NAME
CHECK_CONSTRAINTS CONSTRAINT_SCHEMA
CLIENT_STATISTICS CLIENT
COLLATIONS COLLATION_NAME
COLLATION_CHARACTER_SET_APPLICABILITY COLLATION_NAME
COLUMNS TABLE_SCHEMA
COLUMN_PRIVILEGES TABLE_SCHEMA
ENABLED_ROLES ROLE_NAME
ENGINES ENGINE
EVENTS EVENT_SCHEMA
FILES TABLE_SCHEMA
GEOMETRY_COLUMNS F_TABLE_SCHEMA
GLOBAL_STATUS VARIABLE_NAME
GLOBAL_VARIABLES VARIABLE_NAME
INDEX_STATISTICS TABLE_SCHEMA
INNODB_BUFFER_PAGE POOL_ID
INNODB_BUFFER_PAGE_LRU POOL_ID
INNODB_BUFFER_POOL_STATS POOL_ID
INNODB_CMP page_size
INNODB_CMPMEM page_size
INNODB_CMPMEM_RESET page_size
INNODB_CMP_PER_INDEX database_name
INNODB_CMP_RESET page_size
INNODB_LOCKS lock_id
INNODB_LOCK_WAITS requesting_trx_id
INNODB_METRICS NAME
INNODB_SYS_COLUMNS TABLE_ID
INNODB_SYS_FIELDS INDEX_ID
INNODB_SYS_FOREIGN ID
INNODB_SYS_FOREIGN_COLS ID
INNODB_SYS_INDEXES INDEX_ID
INNODB_SYS_TABLES TABLE_ID
INNODB_SYS_TABLESTATS TABLE_ID
INNODB_SYS_VIRTUAL TABLE_ID
INNODB_TABLESPACES_ENCRYPTION SPACE
INNODB_TRX trx_id
KEYWORDS WORD
KEY_CACHES KEY_CACHE_NAME
KEY_COLUMN_USAGE CONSTRAINT_SCHEMA
OPTIMIZER_COSTS ENGINE
OPTIMIZER_TRACE QUERY
PARAMETERS SPECIFIC_SCHEMA
PARTITIONS TABLE_SCHEMA
PLUGINS PLUGIN_NAME
PROCESSLIST ID
PROFILING QUERY_ID
REFERENTIAL_CONSTRAINTS CONSTRAINT_SCHEMA
ROUTINES ROUTINE_SCHEMA
SCHEMATA SCHEMA_NAME
SCHEMA_PRIVILEGES TABLE_SCHEMA
SESSION_STATUS VARIABLE_NAME
SESSION_VARIABLES VARIABLE_NAME
SPATIAL_REF_SYS SRID
SQL_FUNCTIONS FUNCTION
STATISTICS TABLE_SCHEMA
SYSTEM_VARIABLES VARIABLE_NAME
TABLES TABLE_SCHEMA
TABLESPACES TABLESPACE_NAME
TABLE_CONSTRAINTS CONSTRAINT_SCHEMA
TABLE_PRIVILEGES TABLE_SCHEMA
TABLE_STATISTICS TABLE_SCHEMA
TRIGGERS TRIGGER_SCHEMA
USER_PRIVILEGES GRANTEE
USER_STATISTICS USER
VIEWS TABLE_SCHEMA
select 1 as "must be 1" from information_schema.tables where "ACCOUNTS"=
(select cast(table_name as char) from information_schema.tables
order by table_name limit 1) limit 1;
must be 1
1
select t.table_name, group_concat(t.table_schema, '.', t.table_name),
count(*) as num1
from information_schema.tables t
inner join information_schema.columns c1
on t.table_schema = c1.table_schema AND t.table_name = c1.table_name
where t.table_schema = 'information_schema' and
c1.ordinal_position =
(select isnull(c2.column_type) -
isnull(group_concat(c2.table_schema, '.', c2.table_name)) +
count(*) as num
from information_schema.columns c2 where
c2.table_schema='information_schema' and
(c2.column_type = 'varchar(7)' or c2.column_type = 'varchar(20)')
group by c2.column_type order by num limit 1)
group by t.table_name order by num1, t.table_name;
table_name group_concat(t.table_schema, '.', t.table_name) num1
ALL_PLUGINS information_schema.ALL_PLUGINS 1
APPLICABLE_ROLES information_schema.APPLICABLE_ROLES 1
CHARACTER_SETS information_schema.CHARACTER_SETS 1
CHECK_CONSTRAINTS information_schema.CHECK_CONSTRAINTS 1
CLIENT_STATISTICS information_schema.CLIENT_STATISTICS 1
COLLATIONS information_schema.COLLATIONS 1
COLLATION_CHARACTER_SET_APPLICABILITY information_schema.COLLATION_CHARACTER_SET_APPLICABILITY 1
COLUMNS information_schema.COLUMNS 1
COLUMN_PRIVILEGES information_schema.COLUMN_PRIVILEGES 1
ENGINES information_schema.ENGINES 1
EVENTS information_schema.EVENTS 1
FILES information_schema.FILES 1
GEOMETRY_COLUMNS information_schema.GEOMETRY_COLUMNS 1
GLOBAL_STATUS information_schema.GLOBAL_STATUS 1
GLOBAL_VARIABLES information_schema.GLOBAL_VARIABLES 1
INDEX_STATISTICS information_schema.INDEX_STATISTICS 1
INNODB_BUFFER_PAGE information_schema.INNODB_BUFFER_PAGE 1
INNODB_BUFFER_PAGE_LRU information_schema.INNODB_BUFFER_PAGE_LRU 1
INNODB_BUFFER_POOL_STATS information_schema.INNODB_BUFFER_POOL_STATS 1
INNODB_CMP information_schema.INNODB_CMP 1
INNODB_CMPMEM information_schema.INNODB_CMPMEM 1
INNODB_CMPMEM_RESET information_schema.INNODB_CMPMEM_RESET 1
INNODB_CMP_PER_INDEX information_schema.INNODB_CMP_PER_INDEX 1
INNODB_CMP_RESET information_schema.INNODB_CMP_RESET 1
INNODB_LOCKS information_schema.INNODB_LOCKS 1
INNODB_LOCK_WAITS information_schema.INNODB_LOCK_WAITS 1
INNODB_METRICS information_schema.INNODB_METRICS 1
INNODB_SYS_COLUMNS information_schema.INNODB_SYS_COLUMNS 1
INNODB_SYS_FIELDS information_schema.INNODB_SYS_FIELDS 1
INNODB_SYS_FOREIGN information_schema.INNODB_SYS_FOREIGN 1
INNODB_SYS_FOREIGN_COLS information_schema.INNODB_SYS_FOREIGN_COLS 1
INNODB_SYS_INDEXES information_schema.INNODB_SYS_INDEXES 1
INNODB_SYS_TABLES information_schema.INNODB_SYS_TABLES 1
INNODB_SYS_TABLESTATS information_schema.INNODB_SYS_TABLESTATS 1
INNODB_SYS_VIRTUAL information_schema.INNODB_SYS_VIRTUAL 1
INNODB_TABLESPACES_ENCRYPTION information_schema.INNODB_TABLESPACES_ENCRYPTION 1
INNODB_TRX information_schema.INNODB_TRX 1
KEY_CACHES information_schema.KEY_CACHES 1
KEY_COLUMN_USAGE information_schema.KEY_COLUMN_USAGE 1
OPTIMIZER_COSTS information_schema.OPTIMIZER_COSTS 1
OPTIMIZER_TRACE information_schema.OPTIMIZER_TRACE 1
PARAMETERS information_schema.PARAMETERS 1
PARTITIONS information_schema.PARTITIONS 1
PLUGINS information_schema.PLUGINS 1
PROCESSLIST information_schema.PROCESSLIST 1
PROFILING information_schema.PROFILING 1
REFERENTIAL_CONSTRAINTS information_schema.REFERENTIAL_CONSTRAINTS 1
ROUTINES information_schema.ROUTINES 1
SCHEMATA information_schema.SCHEMATA 1
SCHEMA_PRIVILEGES information_schema.SCHEMA_PRIVILEGES 1
SESSION_STATUS information_schema.SESSION_STATUS 1
SESSION_VARIABLES information_schema.SESSION_VARIABLES 1
SPATIAL_REF_SYS information_schema.SPATIAL_REF_SYS 1
STATISTICS information_schema.STATISTICS 1
SYSTEM_VARIABLES information_schema.SYSTEM_VARIABLES 1
TABLES information_schema.TABLES 1
TABLESPACES information_schema.TABLESPACES 1
TABLE_CONSTRAINTS information_schema.TABLE_CONSTRAINTS 1
TABLE_PRIVILEGES information_schema.TABLE_PRIVILEGES 1
TABLE_STATISTICS information_schema.TABLE_STATISTICS 1
TRIGGERS information_schema.TRIGGERS 1
USER_PRIVILEGES information_schema.USER_PRIVILEGES 1
USER_STATISTICS information_schema.USER_STATISTICS 1
VIEWS information_schema.VIEWS 1
+---------------------------------------+
+---------------------------------------+
+---------------------------------------+
Database: information_schema
| Tables |
| ALL_PLUGINS |
| APPLICABLE_ROLES |
| CHARACTER_SETS |
| CHECK_CONSTRAINTS |
| CLIENT_STATISTICS |
| COLLATIONS |
| COLLATION_CHARACTER_SET_APPLICABILITY |
| COLUMNS |
| COLUMN_PRIVILEGES |
| ENABLED_ROLES |
| ENGINES |
| EVENTS |
| FILES |
| GEOMETRY_COLUMNS |
| GLOBAL_STATUS |
| GLOBAL_VARIABLES |
| INDEX_STATISTICS |
| INNODB_BUFFER_PAGE |
| INNODB_BUFFER_PAGE_LRU |
| INNODB_BUFFER_POOL_STATS |
| INNODB_CMP |
| INNODB_CMPMEM |
| INNODB_CMPMEM_RESET |
| INNODB_CMP_PER_INDEX |
| INNODB_CMP_RESET |
| INNODB_LOCKS |
| INNODB_LOCK_WAITS |
| INNODB_METRICS |
| INNODB_SYS_COLUMNS |
| INNODB_SYS_FIELDS |
| INNODB_SYS_FOREIGN |
| INNODB_SYS_FOREIGN_COLS |
| INNODB_SYS_INDEXES |
| INNODB_SYS_TABLES |
| INNODB_SYS_TABLESTATS |
| INNODB_SYS_VIRTUAL |
| INNODB_TABLESPACES_ENCRYPTION |
| INNODB_TRX |
| KEYWORDS |
| KEY_CACHES |
| KEY_COLUMN_USAGE |
| OPTIMIZER_COSTS |
| OPTIMIZER_TRACE |
| PARAMETERS |
| PARTITIONS |
| PLUGINS |
| PROCESSLIST |
| PROFILING |
| REFERENTIAL_CONSTRAINTS |
| ROUTINES |
| SCHEMATA |
| SCHEMA_PRIVILEGES |
| SESSION_STATUS |
| SESSION_VARIABLES |
| SPATIAL_REF_SYS |
| SQL_FUNCTIONS |
| STATISTICS |
| SYSTEM_VARIABLES |
| TABLES |
| TABLESPACES |
| TABLE_CONSTRAINTS |
| TABLE_PRIVILEGES |
| TABLE_STATISTICS |
| TRIGGERS |
| USER_PRIVILEGES |
| USER_STATISTICS |
| VIEWS |
+---------------------------------------+
+---------------------------------------+
+---------------------------------------+
Database: INFORMATION_SCHEMA
| Tables |
| ALL_PLUGINS |
| APPLICABLE_ROLES |
| CHARACTER_SETS |
| CHECK_CONSTRAINTS |
| CLIENT_STATISTICS |
| COLLATIONS |
| COLLATION_CHARACTER_SET_APPLICABILITY |
| COLUMNS |
| COLUMN_PRIVILEGES |
| ENABLED_ROLES |
| ENGINES |
| EVENTS |
| FILES |
| GEOMETRY_COLUMNS |
| GLOBAL_STATUS |
| GLOBAL_VARIABLES |
| INDEX_STATISTICS |
| INNODB_BUFFER_PAGE |
| INNODB_BUFFER_PAGE_LRU |
| INNODB_BUFFER_POOL_STATS |
| INNODB_CMP |
| INNODB_CMPMEM |
| INNODB_CMPMEM_RESET |
| INNODB_CMP_PER_INDEX |
| INNODB_CMP_RESET |
| INNODB_LOCKS |
| INNODB_LOCK_WAITS |
| INNODB_METRICS |
| INNODB_SYS_COLUMNS |
| INNODB_SYS_FIELDS |
| INNODB_SYS_FOREIGN |
| INNODB_SYS_FOREIGN_COLS |
| INNODB_SYS_INDEXES |
| INNODB_SYS_TABLES |
| INNODB_SYS_TABLESTATS |
| INNODB_SYS_VIRTUAL |
| INNODB_TABLESPACES_ENCRYPTION |
| INNODB_TRX |
| KEYWORDS |
| KEY_CACHES |
| KEY_COLUMN_USAGE |
| OPTIMIZER_COSTS |
| OPTIMIZER_TRACE |
| PARAMETERS |
| PARTITIONS |
| PLUGINS |
| PROCESSLIST |
| PROFILING |
| REFERENTIAL_CONSTRAINTS |
| ROUTINES |
| SCHEMATA |
| SCHEMA_PRIVILEGES |
| SESSION_STATUS |
| SESSION_VARIABLES |
| SPATIAL_REF_SYS |
| SQL_FUNCTIONS |
| STATISTICS |
| SYSTEM_VARIABLES |
| TABLES |
| TABLESPACES |
| TABLE_CONSTRAINTS |
| TABLE_PRIVILEGES |
| TABLE_STATISTICS |
| TRIGGERS |
| USER_PRIVILEGES |
| USER_STATISTICS |
| VIEWS |
+--------------------+
+--------------------+
+--------------------+
Wildcard: inf_rmation_schema
| Databases |
| information_schema |
SELECT table_schema, count(*) FROM information_schema.TABLES WHERE table_schema IN ('mysql', 'INFORMATION_SCHEMA', 'test', 'mysqltest') GROUP BY TABLE_SCHEMA;
table_schema count(*)
information_schema 67
mysql 31
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