to be compiled in
The problem was that on a statically built server an attempt to create
a UDF resulted in a different, but reasonable error ("Can't open shared
library" instead of "UDFs are unavailable with the --skip-grant-tables
option"), which caused a failure for the test case for bug #32020.
Fixed by moving the test case for bug #32020 from skip_grants.test to a
separate test to ensure that it is only run when the server is built
with support for dynamically loaded libraries.
causes out of memory errors
The code in mysql_create_function() and mysql_drop_function() assumed
that the only reason for UDFs being uninitialized at that point is an
out-of-memory error during initialization. However, another possible
reason for that is the --skip-grant-tables option in which case UDF
initialization is skipped and UDFs are unavailable.
The solution is to check whether mysqld is running with
--skip-grant-tables and issue a proper error in such a case.
- BUG#11986: Stored routines and triggers can fail if the code
has a non-ascii symbol
- BUG#16291: mysqldump corrupts string-constants with non-ascii-chars
- BUG#19443: INFORMATION_SCHEMA does not support charsets properly
- BUG#21249: Character set of SP-var can be ignored
- BUG#25212: Character set of string constant is ignored (stored routines)
- BUG#25221: Character set of string constant is ignored (triggers)
There were a few general problems that caused these bugs:
1. Character set information of the original (definition) query for views,
triggers, stored routines and events was lost.
2. mysqldump output query in client character set, which can be
inappropriate to encode definition-query.
3. INFORMATION_SCHEMA used strings with mixed encodings to display object
definition;
1. No query-definition-character set.
In order to compile query into execution code, some extra data (such as
environment variables or the database character set) is used. The problem
here was that this context was not preserved. So, on the next load it can
differ from the original one, thus the result will be different.
The context contains the following data:
- client character set;
- connection collation (character set and collation);
- collation of the owner database;
The fix is to store this context and use it each time we parse (compile)
and execute the object (stored routine, trigger, ...).
2. Wrong mysqldump-output.
The original query can contain several encodings (by means of character set
introducers). The problem here was that we tried to convert original query
to the mysqldump-client character set.
Moreover, we stored queries in different character sets for different
objects (views, for one, used UTF8, triggers used original character set).
The solution is
- to store definition queries in the original character set;
- to change SHOW CREATE statement to output definition query in the
binary character set (i.e. without any conversion);
- introduce SHOW CREATE TRIGGER statement;
- to dump special statements to switch the context to the original one
before dumping and restore it afterwards.
Note, in order to preserve the database collation at the creation time,
additional ALTER DATABASE might be used (to temporary switch the database
collation back to the original value). In this case, ALTER DATABASE
privilege will be required. This is a backward-incompatible change.
3. INFORMATION_SCHEMA showed non-UTF8 strings
The fix is to generate UTF8-query during the parsing, store it in the object
and show it in the INFORMATION_SCHEMA.
Basically, the idea is to create a copy of the original query convert it to
UTF8. Character set introducers are removed and all text literals are
converted to UTF8.
This UTF8 query is intended to provide user-readable output. It must not be
used to recreate the object. Specialized SHOW CREATE statements should be
used for this.
The reason for this limitation is the following: the original query can
contain symbols from several character sets (by means of character set
introducers).
Example:
- original query:
CREATE VIEW v1 AS SELECT _cp1251 'Hello' AS c1;
- UTF8 query (for INFORMATION_SCHEMA):
CREATE VIEW v1 AS SELECT 'Hello' AS c1;
- Crash occured because Event engine is only initialized if
ACLs are used but not properly marked as disabled.
- The patch is to mark the Event engine as DISABLED if no ACLs
are used to avoid access of uninitialized variables.
if --skip-grant-tables specified.
The problem is that there is a check that prevents creating a definer
with empty host name.
In --skip-grant-tables mode this check prevents the user from creating a
trigger/view without explicitly specifying its definer. This happens, because
in --skip-grant-tables mode CURRENT_USER is ''@''. According to Sanja this
check was implemented intentionally.
However, according to the MySQL manual it is possible to specify empty host
name (as well as empty user name). Moreover, the behaviour for stored routines
is different in this aspect -- we allow them to be created with implicit
definer.
Based on this, we believe it is OK to change the behaviour for views to be
similar with the behaviour for stored routines.
--skip-grant-tables. However when deleting functions UDFs list was checked
regardless of whther UDFs are initialized or not. Additional check is added
into free_udf() and find_udf() functions to prevent possible runtime errors.
- Dont perform automatic privilege handling for stored procedures when server is started --skip-grant-tables
- Renamed view_skip_grants to skip_grants and added test cases for this
2005-05-26 16:44:46 +02:00
Renamed from mysql-test/r/view_skip_grants.result (Browse further)
