MySQL 8.0.34 릴리즈 노트

이제 새로운 비밀번호 유효성 검사 시스템 변수를 통해 사용자가 자신의 MySQL 계정 비밀번호를 바꾸려고 할 때 변경해야 하는 최소 문자 수를 구성하고 적용할 수 있습니다. 이 새로운 확인 설정은 현재 비밀번호의 총 문자 수에 대한 백분율입니다. 예를 들어, validate_password.changed_characters_percentage의 값이 50인 경우, 변경하려는 계정 비밀번호에 있는 문자의 절반 이상이 현재 비밀번호에 없어야 하며, 그렇지 않으면 비밀번호가 거부됩니다.

이 새로운 기능은 DBA가 비밀번호 관리를 더욱 완벽하게 제어할 수 있는 여러 기능 중 하나입니다. 자세한 내용은 비밀번호 관리를 참고합니다. (WL #15751)

MySQL 8.0.33에서는, audit_log 플러그인에 JSON 필터 테이블을 어떤 데이터베이스에 저장할 것인지 선택하는 기능이 추가되었습니다. 이제 플러그인 설치 스크립트를 실행할 때 기본 시스템 데이터베이스인 mysql 대신 다른 데이터베이스를 지정할 수 있습니다. 명령줄에서 audit_log_database 서버 시스템 변수(또는 -D database_name)를 대체 데이터베이스 이름과 함께 사용하면 됩니다. 예를 들면:

$> mysql -u root -D database_name -p < audit_log_filter_linux_install.sql

audit_log 플러그인 설치 스크립트 사용에 대한 자세한 내용은, MySQL Enterprise Audit 설치 또는 제거를 참고합니다. (버그 #35252268)

이제 libmysqlclient.so 공유 라이브러리에 개발자가 MySQL 서버 바이너리 로그에 액세스할 수 있는 몇 가지 함수가 추가되었습니다: mysql_binlog_open(), mysql_binlog_fetch() 및 mysql_binlog_close()

기여해 주신 유라 소로킨에게 감사드립니다. (버그 #110658, 버그 #35282154)

호출 함수에서, net->vio가 null인 경우 len이 0으로 초기화되고 다시 변경되지 않는 문제가 있었습니다. 이번 수정을 통해 vio를 역참조하기 전 net을 먼저 검사하는 기능이 추가 되었습니다.
기여해 주신 메타에게 감사드립니다. (버그 #30809590)

특정 코드 경로에서 비동기 클라이언트의 변수가 초기화되지 않는 문제가 있었습니다. 항상 변수를 초기화함으로써 수정하였습니다.

기여해 주신 메타에게 감사드립니다. (버그 #30809590)

마이크로소프트 윈도우: 윈도우의 경우, MSVC_CPPCHECK 지원이 개선되었습니다; 또한 'maintainer' 모드에서 처럼 MSVC 경고를 확인하십시오. 예를 들어, 모든 서드파티 설정이 완료된 후 확인하십시오. (버그 #35283401)

참고: 버그 #34828882.

마이크로소프트 윈도우: 윈도우 빌드의 경우, WIN_DEBUG_NO_INLINE=1 지원을 개선했습니다; 사용량이 라이브러리 제한인 65535개 오브젝트를 초과할 수 있습니다. (버그 #35259704)

번들로 제공되는 로빈 후드 해싱을 v3.8.1에서 v3.11.5로 업그레이드했습니다. (버그 #35448980)

extra/libcbor/doc/source/requirements.txt가 GitHub의 가짜 풀 리퀘스트로 부터 영향을 받으므로 extra/libcbor/doc/ 디렉토리를 제거했습니다. (버그 #35433370)

icu-data-files 패키지의 번들 ICU 파일을 버전 69.1에서 버전 73으로 업데이트했습니다.

(버그 #35353708)

소스 트리에 번들로 제공되는 ZSTD 소스가 1.5.0에서 1.5.5로 업그레이드되었습니다. (버그 #35353698).

TRASH 매크로를 사용하여 내부 MEM_ROOT 클래스 메모리를 가비지로 초기화하여 MEM_ROOT에서 할당된 초기화 메모리를 읽음으로써 발생하는 버그를 쉽게 재현할 수 있도록 합니다. (버그 #35277644)

이제 스택 방향을 설정 시점이 아닌 런타임에 결정하게 되었습니다. (버그 #35181008)

Bison의 최소 버전 요구 사항을 v2.1에서 v3.0.4로 변경했습니다. macOS의 경우 홈브루와 같은 패키지 관리자를 통해 Bison을 설치해야 할 수 있습니다. (버그 #35154645, 버그 #35191333)

macOS에서 Homebrew를 통해 rapidjson을 설치한 경우 MySQL이 컴파일되지 않습니다. 해결 방법은 brew unlink rapidjson이었습니다. (버그 #110736, 버그 #35311140).

참고: 이 문제는 다음의 회귀입니다: 버그 #35006191.

MySQL은 -DWITH_ZLIB=system에서 빌드되지 않습니다; 시스템 zlib 라이브러리를 찾았음에도 불구하고 찾지 못했다고 메세지를 뿌릴 것입니다. (버그 #110727, 버그 #110745, 버그 #35307674, 버그 #35312227)

Performance Schema의 clone_status 테이블의 gtid_executed 컬럼에 사용되던 데이터 타입이 VARCHAR (4096)에서 LONGTEXT로 변경되었습니다. (버그 #109171, 버그 #34828542)

이제 CREATE TABLE 및 ALTER TABLE ... ADD COLUMN 문에서 VARCHAR와 TEXT컬럼의 default 값으로 CURRENT_USER()를 사용할 수 있습니다.

같은 경우에서 SESSION_USER(), USER() 및 SYSTEM_USER() 함수도 지원됩니다. 예를 들어, 다음 구문들의 경우 이제 여기에 표시된 것과 유사하게 작동하며, 정확한 출력은 사용자 환경에 따라 달라집니다:

mysql> SELECT CURRENT_USER();
+-------------------+
| CURRENT_USER()    |
+-------------------+
|  sakila@localhost |
+-------------------+
1 row in set (0.00 sec)

mysql> CREATE TABLE t (
     >  c1 VARCHAR(288) DEFAULT (USER()),
     >  c2 VARCHAR(288) DEFAULT (CURRENT_USER()),
     >  c3 VARCHAR(288) DEFAULT (SESSION_USER()), 
     >  c4 VARCHAR(288) DEFAULT (SYSTEM_USER())
     > );
Query OK, 0 rows affected (0.04 sec)

mysql> INSERT INTO t VALUES ROW();
Query OK, 1 row affected (0.01 sec)

mysql> TABLE t;
+-------------------+-------------------+-------------------+-------------------+
| c1                | c2                | c3                | c4                |
+-------------------+-------------------+-------------------+-------------------+
|  sakila@localhost |  sakila@localhost |  sakila@localhost |  sakila@localhost |
+-------------------+-------------------+-------------------+-------------------+
1 row in set (0.00 sec)

중요 변경 사항: OpenSSL 라이브러리가 번들로 제공되는 플랫폼의 경우, 연결된 MySQL Server용 OpenSSL 라이브러리가 OpenSSL 1.1.1에서 OpenSSL 3.0으로 업데이트 되었습니다. 정확한 버전은 이제 3.0.9입니다. 1.1.1에서 3.0으로의 변경 사항에 대한 자세한 내용은 https://www.openssl.org/docs/man3.0/man7/migration_guide.html 에서 확인할 수 있습니다. (버그 #35475140, WL #15614)

패키징: 이번 릴리즈부터는, 기존에 -el7-x86_64.tar 및 -el7-x86_64.tar.gz 라는 이름을  사용한 바이너리 아카이브 패키지의 이름이 각각 -linux-glibc2.17-x86_64.tar 및 -linux-glibc2.17-x86_64.tar.gz로 변경됩니다. 예를 들어, MySQL 8.0.33을 설치 또는 업그레이드할 때 mysql-8.0.33-el7-x86_64.tar를 사용했다면, MySQL 8.0.34를 설치 또는 업그레이드할 때는 mysql-8.0.34-linux-glibc2.17-x86_64.tar를 사용해야 합니다.

이름이 변경된 것은 이 바이너리들이 glibc2.17 이상을 사용하는 모든 Linux 시스템과 호환된다는 사실을 반영한 것입니다; 여기에는 Enterprise Linux 7, EL8 및 EL9가 포함됩니다.

시스템의 curl 라이브러리에 연결하는 것이 아닌, 자체적으로 curl을 포함하는 바이너리 패키지의 경우 curl 8.1.2를 사용하도록 업그레이드되었습니다. (버그 #35329529)

Important Change: The default value of the connection_memory_chunk_size server system variable, when introduced in MySQL 8.0.28, was mistakenly set at 8912. This fix changes the default to 8192, which is the value originally intended. (Bug #35218020)

NDB Cluster: The fix for a previous issue introduced a slight possibility of unequal string values comparing as equal, if any Unicode 9.0 collations were in use, and the collation hash methods calculated identical hash keys for two unequal strings. (Bug #35168702)

References: See also: Bug #27522732. This issue is a regression of: Bug #30884622.

InnoDB: Possible congestion due to purging a large number of system threads has been fixed. (Bug #35289390, Bug #110685)

InnoDB: ddl::Aligned_buffer now uses the standard memory allocator and not kernel memory management. (Bug #35194732, Bug #110411)

InnoDB: An upgrade from MySQL 5.7 to MySQL 8.0.32 might fail due to deprecated configuration parameters innodb_log_file_size or innodb_log_files_in_group. The workaround is to start MySQL 8.0.32 with --innodb-redo-log-capacity=206158430208. (Bug #35155280)

InnoDB: The rules for aggregating entries in the redo log have been fixed. (Bug #34752625, Bug #108944)

InnoDB: Several errors due to tablespace deletion and the buffer pool have been fixed. (Bug #34330475, Bug #107689)

Packaging; Group Replication: The group replication plugin from the Generic Linux packages did not load on some platforms that lacked a compatible version of tirpc. (Bug #35323208)

Replication: Changes in session_track_gtids were not always propagated correctly. (Bug #35401212)

Replication: By design, all DDL operations (including binary log operations such as purging the binary log) acquire a shared lock on the BACKUP_LOCK object, which helps to prevent simultaneous backup and DDL operations. For binary log operations, we checked whether any locks existed on BACKUP_LOCK but did not check the types of any such locks. This caused problems due to the fact that binary log operations should be prevented only when an exclusive lock is held on the BACKUP_LOCK object, that is, only when a backup is actually in progress, and backups should be prevented when purging the binary log.

Now in such cases, instead of checking for locks held on the BACKUP_LOCK object, we acquire a shared lock on BACKUP_LOCK while purging the binary log. (Bug #35342521)

Replication: In all cases except one, when mysqlbinlog encountered an error while reading an event, it wrote an error message and returned a nonzero exit code, the exception being for the active binary log file (or any binary log where the format_description_log_event had the LOG_EVENT_BINLOG_IN_USE_F flag set), in which case it did not write a message, and returned exit code 0, thus hiding the error.

Now mysqlbinlog suppresses only those errors which are related to truncated events, and when doing so, prints a comment rather than an error message. This fix also improves the help text for the --force-if-open option. (Bug #35083373)

Replication: Compressed binary log event handling was improved. (Bug #33666652)

Replication: A transaction consisting of events each smaller than 1 GiB, but whose total size was larger than 1 GiB, and where compression did not make it smaller than 1 GiB, was still written to the binary log as one event bigger than 1 GiB. This made the binary log unusable; in effect, it was corrupted since neither the server nor other tools such as mysqlbinlog could read it.

Now, when the compressed data grows larger than 1 GiB, we fall back to processing the transaction without any compression. (Bug #33588473)

Group Replication: In a group replication setup, when there was a source of transactions other than the applier channel, the following sequence of events was possible:

This gave rise to the following issue: There was a window wherein the last transaction from Ticket 2 had already marked itself as being executed but had not yet popped the ticket; VC2 popped the ticket instead but never notified any of the participants. This meant that VC1 continued to wait indefinitely for the ticket to change, and with the additional effect that the worker could not be killed.

We fix this by checking for the need to break each second so that this loop is responsive to changes in the loop condition; we also register a new stage, so that the loop is more responsive to kill signals. (Bug #35392640)

References: See also: Bug #35206392, Bug #35374425.

Group Replication: Removed a memory leak discovered in Network_provider_manager::open_xcom_connection(). (Bug #34991101)

Group Replication: When a group action was sent to the group and the connection was killed on the coordinator, group members were in different states, with members which received the coordinated action waiting for the member that executed it, and the member which started execution having nothing to process, which caused problems with coordination of the group.

Now in such cases, we prevent this issue from occurring by causing group actions to wait until all members have completed the action. (Bug #34815537)

Group Replication: Cleanup of resources used by OpenSSL connections created indirectly by group replication was not carried out as expected at all times. We fix this by adding cleanup functionality that can be called at any time such connections are created by group replication. (Bug #34727136)

JSON: When the result of JSON_VALUE() was an empty string and was assigned to a user variable, the user variable could in some cases be set to NULL instead, as shown here:

mysql> SELECT JSON_VALUE('{"fname": "Joe", "lname": ""}', '$.lname') INTO @myvar;
Query OK, 1 row affected (0.01 sec)

mysql> SELECT @myvar = '', @myvar IS NULL;
+-------------+----------------+
| @myvar = '' | @myvar IS NULL |
+-------------+----------------+
|        NULL |              1 |
+-------------+----------------+
1 row in set (0.00 sec)

With this fix, the query just shown now returns (1, 0), as expected. (Bug #35206138)

JSON: Some JSON schemas were not always processed correctly by JSON_SCHEMA_VALID(). (Bug #109296, Bug #34867398)

In rare cases, MySQL server could exit rather than emit an error message as expected. (Bug #35442407)

The internal resource-group enhancement added in MySQL 8.0.31 and refactored in MySQL 8.0.32 is now reverted. (Bug #35434219)

References: Reverted patches: Bug #34702833.

An in-place upgrade from MySQL 5.7 to MySQL 8.0, without a server restart, could result in unexpected errors when executing queries on tables. This fix eliminates the need to restart the server between the upgrade and queries. (Bug #35410528)

A fix in MySQL 8.0.33 made a change for ORDER BY items already resolved so as not to resolve them again (as is usually the case when a derived table is merged), but this did not handle the case in which an ORDER BY item was itself a reference. (Bug #35410465)

References: This issue is a regression of: Bug #34890862.

Changes in session_track_gtids were not always handled correctly. (Bug #35401212)

Some pointers were not always released following statement execution. (Bug #35395965)

Some instances of subqueries within stored routines were not always handled correctly. (Bug #35377192)

Fortified parsing of the network packet data sent by the server to the client. (Bug #35374491)

Encryption enhancements now strengthen compliance and remove the use of deprecated APIs. (Bug #35339886)

When a column reference given by table name and column name was looked up in the function find_item_in_list(), we ignored that the item searched for might not have a table name, as it was not yet resolved. We fix this by making an explicit check for a null table name in the sought-after item. (Bug #35338776)

Deprecated the lz4_decompress and zlib_decompress command-line utilities that exist to support the deprecated mysqlpump command-line utility. (Bug #35328235)

Queries using LIKE '%...%' ran more poorly than in previous versions of MySQL. (Bug #35296563)

In Bounded_queue::push(), when Key_generator::make_sortkey() returns UINT_MAX (error), then no key has been produced; now when this occurs, we no longer update the internal queue.

As part of this fix, push() now returns true on error. (Bug #35237721)

The authentication_oci plugin is fixed to allow federated and provisioned users to connect to a DB System as a mapped Proxy User using an ephemeral key-pair generated through the OCI CLI. (Bug #35232697)

Some queries using common table expressions were not always processed correctly. (Bug #35231475)

The internal function compare_pair_for_nulls() did not always set an explicit return value. (Bug #35217471)

Removed the clang-tidy checks that clash with the MySQL coding style. (Bug #35208735)

Some subqueries using EXISTS in both the inner and outer parts of the query were not handled correctly. (Bug #35201901)

Rotated audit log files now always reset the ID value of the bookmark to zero, rather than continuing the value from the previous file. (Bug #35200070)

Errors were not always propagated correctly when evaluating items to be sorted by filesort. (Bug #35195181)

References: See also: Bug #35145246.

The fix for a previous issue with ROLLUP led to a premature server exit in debug builds. (Bug #35168639)

References: This issue is a regression of: Bug #33830659.

Simplified the implementation of Item_func_make_set::val_str() to make sure that we never try to reuse any of the input arguments, always using the local string buffer instead. (Bug #35154335, Bug #35158340)

When transforming subqueries to a join with derived tables, with the containing query being grouped, we created an extra derived table in which to do the grouping. This process moved the initial select list items from the containing query into the extra derived table, replacing all of the original select list items (other than subqueries, which get their own derived tables) with columns from the extra derived table.

This logic did not handle DEFAULT correctly due to the manner in which default values were modelled internally. This fix adds support for DEFAULT(expression) in queries undergoing the transform previously mentioned. This fix also solves an issue with item names in metadata whereby two occurrences of the same column in the select list were given the same item name as a result of this same transform. (Bug #35150085, Bug #35101169)

A query of the form SELECT * FROM t1 WHERE (SELECT a FROM t2 WHERE t2.a=t1.a + ABS(t2.b)) > 0 should be rejected with Subquery returns more than 1 row, but when the subquery_to_derived optimization was enabled, the transform was erroneously applied and the query returned an incorrect result. (Bug #35101630)

Handling of certain potentially conflicting GRANT statements has been improved. (Bug #35089304)

A query using both MEMBER OF() and ORDER BY DESC returned only a partial result set following the creation of a multi-valued index on a JSON column. This is similar to an issue fixed in MySQL 8.0.30, but with the addition of the ORDER BY DESC clause to the prblematic query. (Bug #35012146)

References: See also: Bug #106621, Bug #33917625.

The debug server asserted on certain operations involving DECIMAL values. (Bug #34973932)

All instances of adding and replacing expressions in the select list when transforming subqueries to use derived tables and joins have been changed so that their reference counts are maintained properly. (Bug #34927110)

Index Merge (see Index Merge Optimization) should favor ROR-union plans (that is, using RowID Ordered Retrieval) over sort-union plans if they have similar costs, since sort-union requires additionally sorting of the rows by row ID whereas ROR-union does not.

For each part of a WHERE clause containing an OR condition, the range optimizer gets the best range scan possible and uses all these range scans to build an index merge scan (that is, a sort-union scan). If it finds that all the best range scans are also ROR-scans, the range optimizer always proposes a ROR-union scan because it is always cheaper than a sort-union scan. Problems arose when the best range scan for any one part of an OR condition is not a ROR-scan, in which case, the range optimizer always chose sort-union. This was true even in cases, where it might be advantageous to choose a ROR-scan (even though it might not be the best range scan to handle one part of the OR condition), since this would eleminate any need to sort the rows by row ID.

Now, in such cases, when determining the best range scan, the range optimizer also detects whether there is any possible ROR-scan, and uses this information to see whether each part of the OR condition has at least one possible ROR-scan. If so, we rerun the range optimizer to obtain the best ROR-scan for handling each part of the OR condition, and to make a ROR-union path. We then compare this cost with the cost of a sort-union when proposing the final plan. (Bug #34826692, Bug #35302794)

Selecting from a view sometimes raised the error Illegal mix of collations ... for operation '=' when the collation used in the table or tables from which the view definition selected did not match the current session value of collation_connection. (Bug #34801210)

Valid MySQL commands (use and status) and C API functions (mysql_refresh, mysql_stat, mysql_dump_debug_info, mysql_ping, mysql_set_server_option, mysql_list_processes, and mysql_reset_connection) could write an error message to the audit log, even though running the command or calling the function emitted no such error. (Bug #33966181)

Increased the maximum fixed array size to 8192 instead of 512. This fixes an issue with mysqladmin extended status requests, which can exceed 512 entries.

Our thanks to Meta for the contribution. (Bug #30810617)

The mysqldump --column-statistics option attempted to select from information_schema.column_statistics against MySQL versions before 8.0.2, but this now generates the warning column statistics not supported by the server and sets the option to false.

Our thanks to Meta for the contribution. (Bug #28782417)

The function used by MySQL to get the length of a directory name was enhanced. (Bug #28047376)

Executing a query with an implicit aggregation should return exactly one row, unless the query has a HAVING clause that filters out the row, but a query with a HAVING clause which evaluated to FALSE sometimes ignored this, and returned a row regardless. (Bug #14272020)

For a query with a derived condition pushdown where a column in the condition needs to be replaced, a matching item could not found, even when known to be present, when the replacement item was wrapped in a ROLLUP while the matching item was not. (Bug #111665, Bug #35570065)

References: This issue is a regression of: Bug #33349994.

The presence of an unused window function in a query, along with an ORDER BY that could have been eliminated, led to an unplanned server exit. (Bug #111585, Bug #35168639, Bug #35204224, Bug #35545377)

References: This issue is a regression of: Bug #35118579.

ORDER BY RANDOM_BYTES() had no effect on query output. (Bug #111252, Bug #35148945, Bug #35457136)

Fixed an issue which could occur when loading user-defined functions. (Bug #110576, Bug #35242734)

Concurrent execution of FLUSH STATUS, COM_CHANGE_USER, and SELECT FROM I_S.PROCESSLIST could result in a deadlock. A similar issue was observed for concurrent execution of COM_STATISTICS, COM_CHANGE_USER, and SHOW PROCESSLIST.

Our thanks to Dmitry Lenev for the contribution. (Bug #110494, Bug #35218030)

The mysqldump utility could generate invalid INSERT statements for generated columns. (Bug #110462, Bug #35208605)

During optimization, range-select tree creation uses logic which differs based on the left-hand side of the IN() predicate. For a field item, each value on the right-hand side is added to an OR tree to create the necessary expression. In the case of a row item comparison (example: WHERE (a,b) IN ((n1,m1), (n2, m2), ...)), an expression in disjunctive normal form (DNF) is needed. A DNF expression is created by adding an AND tree with column values to an OR tree for each set of RHS values, but instead the OR tree was added to the AND tree causing the tree merge to require exponential time due to O(n²) runtime complexity. (Bug #108963, Bug #34758905)

When using SELECT to create a table and the statement has an expression of type GEOMETRY, MySQL could generate an empty string as the column value by default. To resolve this issue, MySQL no longer generates default values for columns of type GEOMETRY under these circumstances. Our thanks to Tencent for the contribution. (Bug #107996, Bug #34426943)

For index skip scans, the first range read set an end-of-range value to indicate the end of the first range, but the next range read did not clear the stale end-of-range value and applies this stale value to the current range. Since the indicated end-of-range boundary had already been crossed in the previous range read, this caused the reads to stop, causing multiple rows to be missed in the result.

We fix this by making sure in such cases that the old end-of-range value is cleared. (Bug #107460, Bug #34235624, Bug #34982949)