Bug#18282 "INFORMATION_SCHEMA.TABLES provides inconsistent info about invalid views"
This bug caused crashes or resulted in wrong data being returned
when one tried to obtain information from I_S tables about views
using stored functions.
It was caused by the fact that we were using LEX representing
statement which were doing select from I_S tables as active LEX
when contents of I_S table were built. So state of this LEX both
affected and was affected by open_tables() calls which happened
during this process. This resulted in wrong behavior and in
violations of some of invariants which caused crashes.
This fix tries to solve this problem by properly saving/resetting
and restoring part of LEX which affects and is affected by the
process of opening tables and views in get_all_tables() routine.
To simplify things we separated this part of LEX in a new class
and made LEX its descendant.
Crash happened when one selected data from one of INFORMATION_SCHEMA
tables and in order to build its contents server had to open view which
used stored function and table or view on which one had not global or
database-level privileges (e.g. had only table-level or had no
privileges at all).
The crash was caused by usage of check_grant() function, which assumes
that either number of tables to be inspected by it is limited explicitly
or table list used and thd->lex->query_tables_own_last value correspond
to each other (the latter should be either 0 or point to next_global
member of one of elements of this table list), in conditions when
above assumptions were not true. This fix just explicitly limits
number of tables to be inspected. Other negative effects which are
caused by the fact that thd->lex->query_tables_own_last might not
be set properly during processing of I_S tables are less disastrous
and will be reported and fixed separetely.
post-review change - use pointer instead of copy on the stack.
WL#1034 (Internal CRON)
This patch adds INFORMATION_SCHEMA.EVENTS table with the following format:
EVENT_CATALOG - MYSQL_TYPE_STRING (Always NULL)
EVENT_SCHEMA - MYSQL_TYPE_STRING (the database)
EVENT_NAME - MYSQL_TYPE_STRING (the name)
DEFINER - MYSQL_TYPE_STRING (user@host)
EVENT_BODY - MYSQL_TYPE_STRING (the body from mysql.event)
EVENT_TYPE - MYSQL_TYPE_STRING ("ONE TIME" | "RECURRING")
EXECUTE_AT - MYSQL_TYPE_TIMESTAMP (set for "ONE TIME" otherwise NULL)
INTERVAL_VALUE - MYSQL_TYPE_LONG (set for RECURRING otherwise NULL)
INTERVAL_FIELD - MYSQL_TYPE_STRING (set for RECURRING otherwise NULL)
SQL_MODE - MYSQL_TYPE_STRING (for now NULL)
STARTS - MYSQL_TYPE_TIMESTAMP (starts from mysql.event)
ENDS - MYSQL_TYPE_TIMESTAMP (ends from mysql.event)
STATUS - MYSQL_TYPE_STRING (ENABLED | DISABLED)
ON_COMPLETION - MYSQL_TYPE_STRING (NOT PRESERVE | PRESERVE)
CREATED - MYSQL_TYPE_TIMESTAMP
LAST_ALTERED - MYSQL_TYPE_TIMESTAMP
LAST_EXECUTED - MYSQL_TYPE_TIMESTAMP
EVENT_COMMENT - MYSQL_TYPE_STRING
SQL_MODE is NULL for now, because the value is still not stored in mysql.event .
Support will be added as a fix for another bug.
This patch also adds SHOW [FULL] EVENTS [FROM db] [LIKE pattern]
1. SHOW EVENTS shows always only the events on the same user,
because the PK of mysql.event is (definer, db, name) several
users may have event with the same name -> no information disclosure.
2. SHOW FULL EVENTS - shows the events (in the current db as SHOW EVENTS)
of all users. The user has to have PROCESS privilege, if not then
SHOW FULL EVENTS behave like SHOW EVENTS.
3. If [FROM db] is specified then this db is considered.
4. Event names can be filtered with LIKE pattern.
SHOW EVENTS returns table with the following columns, which are subset of
the data which is returned by SELECT * FROM I_S.EVENTS
Db
Name
Definer
Type
Execute at
Interval value
Interval field
Starts
Ends
Status
1) Fixes breakage in embedded server build for XMLPath push.
2) Hides PARTITION engine from view.
3) Add ENGINES information schema (and it should now be clear from this patch on how to turn any show command into an information schema).
"Triggers have the wrong namespace"
"Triggers: duplicate names allowed"
"Triggers: CREATE TRIGGER does not accept fully qualified names"
"SHOW TRIGGERS"
