Index values for row_start/row_end was wrongly calculated for inplace
ALTER for some layout of virtual fields.
Possible impact
1. history row is not detected upon build clustered index for
inplace ALTER which may lead to duplicate key errors on
auto-increment and FTS index add.
2. foreign key constraint may falsely fail.
3. after inplace ALTER before server restart trx-based system
versioning can cause server crash or incorrect data written upon
UPDATE.
The patch for "MDEV-25440: Indexed CHAR ... broken with NO_PAD collations"
fixed these scenarios from MDEV-26743:
- Basic latin letter vs equal accented letter
- Two letters vs equal (but space padded) expansion
However, this scenario was still broken:
- Basic latin letter (but followed by an ignorable character)
vs equal accented letter
Fix:
When processing for a NOPAD collation a string with trailing ignorable
characters, like:
'<non-ignorable><ignorable><ignorable>'
the string gets virtually converted to:
'<non-ignorable><ignorable><ignorable><space><space><space>...'
After the fix the code works differently in these two cases:
1. <space> fits into the "nchars" limit
2. <space> does not fit into the "nchars" limit
Details:
1. If "nchars" is large enough (4+ in this example),
return weights as follows:
'[weight-for-non-ignorable, 1 char] [weight-for-space-character, 3 chars]'
i.e. the weight for the virtual trailing space character now indicates
that it corresponds to total 3 characters:
- two ignorable characters
- one virtual trailing space character
2. If "nchars" is small (3), then the virtual trailing space character
does not fit into the "nchar" limit, so return 0x00 as weight, e.g.:
'[weight-for-non-ignorable, 1 char] [0x00, 2 chars]'
Adding corresponding MTR tests and unit tests.
Problem:
The file backup-my.cnf from the backup directory was loaded by
"mariabackup --prepare" only in case of the explicit --target-dir given.
It was not loaded from the default directory ./xtrabackup_backupfiles/
in case if the explicit --target-dir was missing.
In other words, it worked as follows:
1. When started as "mariabackup --prepare --target-dir=DIR", mariabackup:
a. loads defaults from "DIR/backup-my.cnf"
b. processes data files in the specified directory DIR
2. When started as "mariabackup --prepare", mariabackup:
a. does not load defaults from "./xtrabackup_backupfiles/backup-my.cnf"
b. processes data files in the default directory "./xtrabackup_backupfiles/"
This patch fixes the second scenario, so it works as follows:
2. When started as "mariabackup --prepare", mariabackup:
a. loads defaults from "./xtrabackup_backupfiles/backup-my.cnf"
b. processes data files in the default directory "./xtrabackup_backupfiles/"
This change fixes (among others) the problem with the
"Can't open shared library '/file_key_management.so'" error
reported when "mariabackup --prepare" is used without --target-dir
in combinaton with the encryption plugin.
The crash happened with an indexed virtual column whose
value is evaluated using a function that has a different meaning
in sql_mode='' vs sql_mode=ORACLE:
- DECODE()
- LTRIM()
- RTRIM()
- LPAD()
- RPAD()
- REPLACE()
- SUBSTR()
For example:
CREATE TABLE t1 (
b VARCHAR(1),
g CHAR(1) GENERATED ALWAYS AS (SUBSTR(b,0,0)) VIRTUAL,
KEY g(g)
);
So far we had replacement XXX_ORACLE() functions for all mentioned function,
e.g. SUBSTR_ORACLE() for SUBSTR(). So it was possible to correctly re-parse
SUBSTR_ORACLE() even in sql_mode=''.
But it was not possible to re-parse the MariaDB version of SUBSTR()
after switching to sql_mode=ORACLE. It was erroneously mis-interpreted
as SUBSTR_ORACLE().
As a result, this combination worked fine:
SET sql_mode=ORACLE;
CREATE TABLE t1 ... g CHAR(1) GENERATED ALWAYS AS (SUBSTR(b,0,0)) VIRTUAL, ...;
INSERT ...
FLUSH TABLES;
SET sql_mode='';
INSERT ...
But the other way around it crashed:
SET sql_mode='';
CREATE TABLE t1 ... g CHAR(1) GENERATED ALWAYS AS (SUBSTR(b,0,0)) VIRTUAL, ...;
INSERT ...
FLUSH TABLES;
SET sql_mode=ORACLE;
INSERT ...
At CREATE time, SUBSTR was instantiated as Item_func_substr and printed
in the FRM file as substr(). At re-open time with sql_mode=ORACLE, "substr()"
was erroneously instantiated as Item_func_substr_oracle.
Fix:
The fix proposes a symmetric solution. It provides a way to re-parse reliably
all sql_mode dependent functions to their original CREATE TABLE time meaning,
no matter what the open-time sql_mode is.
We take advantage of the same idea we previously used to resolve sql_mode
dependent data types.
Now all sql_mode dependent functions are printed by SHOW using a schema
qualifier when the current sql_mode differs from the function sql_mode:
SET sql_mode='';
CREATE TABLE t1 ... SUBSTR(a,b,c) ..;
SET sql_mode=ORACLE;
SHOW CREATE TABLE t1; -> mariadb_schema.substr(a,b,c)
SET sql_mode=ORACLE;
CREATE TABLE t2 ... SUBSTR(a,b,c) ..;
SET sql_mode='';
SHOW CREATE TABLE t1; -> oracle_schema.substr(a,b,c)
Old replacement names like substr_oracle() are still understood for
backward compatibility and used in FRM files (for downgrade compatibility),
but they are not printed by SHOW any more.
This imports and adapts a number of MySQL 5.7 test cases that are
applicable to MariaDB.
Some tests for old bug fixes are not that relevant because the code
has been refactored since then (especially starting with
MariaDB Server 10.6), and the tests would not reproduce the
original bug if the fix was reverted.
In the test innodb_fts.opt, there are many duplicate MATCH ranks, which
would make the results nondeterministic. The test was stabilized by
changing some LIMIT clauses or by adding sorted_result in those cases
where the purpose of a test was to show that no sorting took place
in the server.
In the test innodb_fts.phrase, MySQL 5.7 would generate FTS_DOC_ID that
are 1 larger than in MariaDB. In innodb_fts.index_table the difference is 2.
This is because in MariaDB, fts_get_next_doc_id() post-increments
cache->next_doc_id, while MySQL 5.7 pre-increments it.
Reviewed by: Thirunarayanan Balathandayuthapani
In some cases "SHOW PROCESSLIST" could show "Reset for next command"
as State, even if the previous query had finished properly.
Fixed by clearing State after end of command and also setting the State
for the "Connect" command.
Other things:
- Changed usage of 'thd->set_command(COM_SLEEP)' to
'thd->mark_connection_idle()'.
- Changed thread_state_info() to return "" instead of NULL. This is
just a safety measurement and in line with the logic of the
rest of the function.
Binary logging is now disabled for the queries run by SQL SERVICE.
The binlogging can be turned on with the 'SET SQL_LOG_BIN=On' query.
Conflicts:
sql/sql_prepare.cc
Conflicts:
sql/sql_prepare.cc
The reason was that Event e11 was re-executed before
"ALTER EVENT e11 DISABLE" had been executed.
Fixed by increasing re-schedule time
Other things:
- Removed double accounting of 'execution_count'. It was incremented in
top->mark_last_executed(thd) that was executed a few lines earlier.
There where two errors left from the previous fix.
- subselect.test assumes that mysql.slow_log is empty. This was not
enforced.
- subselect.test dropped a file that does not exists (for safety).
This was fixed by ensuring we don't get a warning if the file does
not exist.
Before MariaDB 10.3.5, the binlog position was stored in the TRX_SYS page,
while after it is stored in rollback segments. There is code to read the
legacy position from TRX_SYS to handle upgrades. The problem was if the
legacy position happens to compare larger than the position found in
rollback segments; in this case, the old TRX_SYS position would incorrectly
be preferred over the newer position from rollback segments.
Fixed by always preferring a position from rollback segments over a legacy
position.
Signed-off-by: Kristian Nielsen <knielsen@knielsen-hq.org>
This commit can cause the wrong (old) binlog position to be recovered by
mariabackup --prepare. It implements that the value of the FIL_PAGE_LSN is
compared to determine which binlog position is the last one and should be
recoved. However, it is not guaranteed that the FIL_PAGE_LSN order matches the
commit order, as is assumed by the code. This is because the page LSN could be
modified by an unrelated update of the page after the commit.
In one example, the recovery first encountered this in trx_rseg_mem_restore():
lsn=27282754 binlog position (./master-bin.000001, 472908)
and then later:
lsn=27282699 binlog position (./master-bin.000001, 477164)
The last one 477164 is the correct position. However, because the LSN
encountered for the first one is higher, that position is recovered instead.
This results in too old binlog position, and a newly provisioned slave will
start replicating too early and get duplicate key error or similar.
Signed-off-by: Kristian Nielsen <knielsen@knielsen-hq.org>
Revert the patch for MDEV-18917, which removed this functionality.
This restores that mariabackup --prepare recovers the transactional
binlog position from the redo log, and writes it to the file
xtrabackup_binlog_pos_innodb.
This position is updated only on every InnoDB commit. This means that
if the last event in the binlog at the time of backup is a DDL or
non-transactional update, the recovered position from --no-lock will
be behind the state of the backup.
Signed-off-by: Kristian Nielsen <knielsen@knielsen-hq.org>
Make profiler to play a bit better with memory allocators. Test suite can not be included because it lead to non free memory on shutdown (IMHO OK for memory shortage emulation)
As alternetive all this should be rewritten and ability to return errors on upper level should be added.
In commit 75e82f71f1 the code to
rename internal tables for FULLTEXT INDEX that had been
created on Microsoft Windows using incompatible names
was removed. Let us also remove the related fault injection.
Problem:
=======
- InnoDB fails to find the foreign key index for the newly
added foreign key relation. This is caused by commit
5f09b53bdb (MDEV-31086).
FIX:
===
In check_col_is_in_fk_indexes(), while iterating through
the newly added foreign key relationship, InnoDB should
consider that foreign key relation may not have foreign index
when foreign key check is disabled.
Dyncol functions like column_create() encode the
current character set inside the value.
So they cannot be used with --view-protocol.
This patch changes only --disable_view_protocol to
--disable_service_connection.
This bug affected only multi-table update statements and in very rare
cases: one of the tables used at the top level of the statement must be
a derived table containg a row construct with a subquery including hanging
CTE.
Before this patch was applied the function prepare_unreferenced() of the
class With_element when invoked for the the hangin CTE did not properly
restored the value of thd->lex->context_analysis_only. As a result it
became 0 after the call of this function.
For a query affected by the bug this function is called when
JOIN::prepare() is called for the subquery with a hanging CTE. This happens
when Item_row::fix_fields() calls fix_fields() for the subquery. Setting
the value of thd->lex->context_analysis_only forces the caller function
Item_row::fix_fields() to invoke the virtual method is_null() for the
subquery that leads to execution of it. It causes an assertion failure
because the call of Item_row::fix_fields() happens during the invocation
of Multiupdate_prelocking_strategy::handle_end() that calls the function
mysql_derived_prepare() for the derived table used by the UPDATE at the
time when proper locks for the statement tables has not been acquired yet.
With this patch the value of thd->lex->context_analysis_only is restored
to CONTEXT_ANALYSIS_ONLY_DERIVED that is set in the function
mysql_multi_update_prepare().
Approved by Oleksandr Byelkin <sanja@mariadb.com>
The MTR test rpl.rpl_semi_sync_slave_compressed_protocol scans the
log file to ensure there is no magic number error. It attempts to
only scan the log files of the current test; however, the variable
which controls this, , is initialized incorrectly,
and it thereby scans the entire log file, which includes output from
prior tests. This causes it to fail if a test which expects this
error runs previously on the same worker.
This patch fixes the assert_only_after so the test only scans
through its own log contents.
The test rpl.rpl_sql_thd_start_errno_cleared can lose a debug_sync
signal, as there is a RESET immediately following a SIGNAL. When the
signal is lost, the sql_thread is stuck in a WAIT_FOR clause until
it times out, resulting in long test times (albeit still
successful).
This patch extends the test to ensure the debug_sync signal was
received before issuing the RESET
Item_char_typecast::print() did not print the "binary" keyword
in such cases:
CAST('a' AS CHAR CHARACTER SET latin1 BINARY)
This caused a difference in "mtr" vs "mtr --view-protocol"
This patch corrects the fix for MDEV-32369. No Item_direct_ref_to_item
objects should be allocated at the optimizer phase after permanent
rewritings have been done.
The patch also adds another test case for MDEV-32369 that uses MyISAM
with more than one row.
Approved by Rex Johnston <rex.johnston@mariadb.com>
This commit fixes several bugs in error handling around disk full when
writing the statement/transaction binlog caches:
1. If the error occurs during a non-transactional statement, the code
attempts to binlog the partially executed statement (as it cannot roll
back). The stmt_cache->error was still set from the disk full error. This
caused MYSQL_BIN_LOG::write_cache() to get an error while trying to read the
cache to copy it to the binlog. This was then wrongly interpreted as a disk
full error writing to the binlog file. As a result, a partial event group
containing just a GTID event (no query or commit) was binlogged. Fixed by
checking if an error is set in the statement cache, and if so binlog an
INCIDENT event instead of a corrupt event group, as for other errors.
2. For LOAD DATA LOCAL INFILE, if a disk full error occured while writing to
the statement cache, the code would attempt to abort and read-and-discard
any remaining data sent by the client. The discard code would however
continue trying to write data to the statement cache, and wrongly interpret
another disk full error as end-of-file from the client. This left the client
connection with extra data which corrupts the communication for the next
command, as well as again causing an corrupt/incomplete event to be
binlogged. Fixed by restoring the default read function before reading any
remaining data from the client connection.
Reviewed-by: Andrei Elkin <andrei.elkin@mariadb.com>
Signed-off-by: Kristian Nielsen <knielsen@knielsen-hq.org>
Updates to specific replication system variables need to target the
active primary connection to support multi-source replication. These
variables use the Sys_var_multi_source_ulonglong type. This class
uses offsets of the Master_info C++ class to generalize access to
its member variables.
The problem is that the Master_info class is not of standard layout,
and neither are many of its member variables, e.g. rli and
rli->relay_log. Because the class is not of standard layout, using
offsets to access member variables invokes undefined behavior.
This patch changes how Sys_var_multi_source_ulonglong accesses the
member variables of Master_info from using parameterized memory
offsets to “getter” function pointers.
Note that the size parameter and assertion are removed, as they are
no longer needed because the condition is guaranteed by compiler
type-safety checks.
Reviewed By:
============
Kristian Nielsen <knielsen@knielsen-hq.org>
This commit addresses column naming issues with CTEs in the use of prepared
statements and stored procedures. Usage of either prepared statements or
procedures with Common Table Expressions and column renaming may be affected.
There are three related but different issues addressed here.
1) First execution issue. Consider the following
prepare s from "with cte (col1, col2) as (select a as c1, b as c2 from t
order by c1) select col1, col2 from cte";
execute s;
After parsing, items in the select are named (c1,c2), order by (and group by)
resolution is performed, then item names are set to (col1, col2).
When the statement is executed, context analysis is again performed, but
resolution of elements in the order by statement will not be able to find c1,
because it was renamed to col1 and remains this way.
The solution is to save the names of these items during context resolution
before they have been renamed. We can then reset item names back to those after
parsing so first execution can resolve items referred to in order and group by
clauses.
2) Second Execution Issue
When the derived table contains more than one select 'unioned' together we could
reasonably think that dealing with only items in the first select (which
determines names in the resultant table) would be sufficient. This can lead to
a different problem. Consider
prepare st from "with cte (c1,c2) as
(select a as col1, sum(b) as col2 from t1 where a > 0 group by col1
union select a as col3, sum(b) as col4 from t2 where b > 2 group by col3)
select * from cte where c1=1";
When the optimizer (only run during the first execution) pushes the outside
condition "c1=1" into every select in the derived table union, it renames the
items to make the condition valid. In this example, this leaves the first item
in the second select named 'c1'. The second execution will now fail 'group by'
resolution.
Again, the solution is to save the names during context analysis, resetting
before subsequent resolution, but making sure that we save/reset the item
names in all the selects in this union.
3) Memory Leak
During parsing Item::set_name() is used to allocate memory in the statement
arena. We cannot use this call during statement execution as this represents
a memory leak. We directly set the item list names to those in the column list
of this CTE (also allocated during parsing).
Approved by Igor Babaev <igor@mariadb.com>
For some reason, in embedded server, a command
let $a=`$query`
ignores local context. Make a workaround: use SET STATEMENT to set
debug_dbug in the same statement.
This patch fixes a performance regression introduced in the patch for the
bug MDEV-21104. The performance regression could affect queries for which
join buffer was used for an outer join such that its on expression from
which a conjunctive condition depended only on outer tables can be
extracted. If the number of records in the join buffer for which this
condition was false greatly exceeded the number of other records the
slowdown could be significant.
If there is a conjunctive condition extracted from the ON expression
depending only on outer tables this condition is evaluated when interesting
fields of each survived record of outer tables are put into the join buffer.
Each such set of fields for any join operation is supplied with a match
flag field used to generate null complemented rows. If the result of the
evaluation of the condition is false the flag is set to MATCH_IMPOSSIBLE.
When looking in the join buffer for records matching a record of the
right operand of the outer join operation the records with such flags
are not needed to be unpacked into record buffers for evaluation of on
expressions.
The patch for MDEV-21104 fixing some problem of wrong results when
'not exists' optimization by mistake broke the code that allowed to
ignore records with the match flag set to MATCH_IMPOSSIBLE when looking
for matching records. As a result such records were unpacked for each
record of the right operand of the outer join operation. This caused
significant execution penalty in some cases.
One of the test cases added in the patch can be used only for demonstration
of the restored performance for the reported query. The second test case is
needed to demonstrate the validity of the fix.
