Addendum to thr fix for bug 30000:
show procedure/function code defined only in debug builds
show_check.test:
Addendum to thr fix for bug 30000:
show procedure/function code defined only in debug builds
SHOW CREATE TABLE or SELECT FROM I_S.
This is the last patch for this bug, which depends on the big
CS patch and was pending.
The problem was that SHOW CREATE statements returned original
queries in the binary character set. That could cause the query
to be unreadable.
The fix is to use original character_set_client when sending
the original query to the client. In order to preserve the query
in mysqldump, 'binary' character set results should be set when
issuing SHOW CREATE statement. If either source or destination
character set is 'binary' , no conversion is performed.
The idea is that since the source character set is no longer
'binary', we fix the destination character set to still produce
valid dumps.
- 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;
SHOW CREATE TABLE or SELECT FROM I_S.
Actually, the bug discovers two problems:
- the original query is not preserved properly. This is the problem
of BUG#16291;
- the resultset of SHOW CREATE TABLE statement is binary.
This patch fixes the second problem for the 5.0.
Both problems will be fixed in 5.1.
An attempt to open file with name '????????.frm'
can produce different errors:
- ER_NO_SUCH_TABLE on Unix
- ER_FILE_NOT_FOUND on Windows
because QUESTION MARK has special meaning on Windows.
Make sure that any of these two errors happens.
Problem: crash on attempt to open a table
having "#mysql50#" prefix in db or table name.
Fix: This prefix is reserved for "mysql_upgrade"
to access 5.0 tables whose file names are not encoded
according to "5.1 tablename to filename encoded".
Don't try open tables whose db name or table name
has this prefix.
Before this fix, the command SHOW ENGINE <name> STATUS would:
- print a warning if the engine name is unknown,
- proceed and implement the same behavior as SHOW ENGINE ALL STATUS,
and list the status of all the storage engines registered.
In particular, this behavior caused confusion about the command :
SHOW ENGINE MUTEX STATUS, which as a side effect would print the status
of the innodb engine when that engine is registered.
Also, before this fix, every time an unknown engine name was substituted by
the default engine (which happen unless SQL_MODE NO_ENGINE_SUBSTITUTION is
set), a malformed warning was raised.
For example, the command ALTER TABLE T1 ENGINE = X would print :
Warnings:
Error 1286 Unknown table engine 'X'
With this fix:
SHOW ENGINE <name> STATUS|LOGS|MUTEX
always fails with an error when the engine <name> is unknown.
For other commands, warnings about unknown engines are raised as:
Warnings:
Warning 1286 Unknown table engine 'X'
In other words, engine substitution never affect the SHOW ENGINE command,
since this would lead to very confusing results.
Problem: The Table_type column of "SHOW FULL TABLES" displayed
"ERROR" instead of "BASE TABLE" for tables having non-ascii
characters in their names.
Reason: tablename to filename encoding was missing, so
mysql_frm_type() tried to open a wrong file name.
Fix: adding tablename to filename encoding
Post-commit issues fixed
* Test results for other tests fixed due to added error #s
* Memory allocation/free issues found with running with valgrind
* Fix to mysql-test-run shell script to run federated_server test (installs
mysql.servers table properly)
Moved .progress files into the log directory
Moved 'cluster' database tables into the MySQL database, to not have 'cluster' beeing a reserved database name
Fixed bug where mysqld got a core dump when trying to use a table created by MySQL 3.23
Fixed some compiler warnings
Fixed small memory leak in libmysql
Note that this doesn't changeset doesn't include the new mysqldump.c code required to run some tests. This will be added when I merge 5.0 to 5.1
Do not consider SHOW commands slow queries, just because they don't use proper indexes.
This bug fix is not needed in 5.1, and the code changes will be null merged. However, the test cases will be propogated up to 5.1.
Set a flag when a SHOW command is parsed, and check it in log_slow_statement(). SHOW commands are not counted as slow queries, even if they use table scans.
Identifiers with embedded escape characters were not handled correctly by
some SHOW statements due to some old code that was doing some extra unescaping.
'conc_sys' test
Concurrent execution of SELECT involing at least two INFORMATION_SCHEMA
tables, DROP DATABASE statement and DROP TABLE statement could have
resulted in stalled connection for this SELECT statement.
The problem was that for the first query of a join there was a race
between select from I_S.TABLES and DROP DATABASE, and the error (no
such database) was prepared to be send to the client, but the join
processing was continued. On second query to I_S.COLUMNS there was a
race with DROP TABLE, but this error (no such table) was downgraded to
warning, and thd->net.report_error was reset. And so neither result
nor error was sent to the client.
The solution is to stop join processing once it is clear we are going
to report a error, and also to downgrade to warnings file system errors
like 'no such database' (unless we are in the 'SHOW' command), because
I_S is designed not to use locks and the query to I_S should not abort
if something is dropped in the middle.
No test case is provided since this bug is a result of a race, and is
timing dependant. But we test that plain SHOW TABLES and SHOW COLUMNS
give a error if there is no such database or a table respectively.
The problem was that we restored SQL_CACHE, SQL_NO_CACHE flags in SELECT
statement from internal structures based on value set later at runtime, not
the original value set by the user.
The solution is to remember that original value.
Under row-based replication, DELETE FROM will now always be
replicated as individual row deletions, while TRUNCATE TABLE will
always be replicated as a statement.
