利用 mysqlsh 客户端检查升级 MySQL 8.0 兼容性

./mysqlsh  -S /tmp/mysql_mysql57_1.sock -- util check-for-server-upgrade 
--config-path=/etc/my_57_1.cnf

The MySQL server at /tmp%2Fmysql_mysql57_1.sock, version 5.7.42-log - MySQL
Community Server (GPL), will now be checked for compatibility issues for
upgrade to MySQL 8.0.41...

1) Usage of old temporal type
  No issues found

2) MySQL 8.0 syntax check for routine-like objects
  No issues found

3) Usage of db objects with names conflicting with new reserved keywords
  Warning: The following objects have names that conflict with new reserved
    keywords. Ensure queries sent by your applications use `quotes` when
    referring to them or they will result in errors.
  More information:
    https://dev.mysql.com/doc/refman/en/keywords.html

  test.reserved_demo.window - Column name

4) Usage of utf8mb3 charset
  Warning: The following objects use the utf8mb3 character set. It is
    recommended to convert them to use utf8mb4 instead, for improved Unicode
    support.
  More information:
    https://dev.mysql.com/doc/refman/8.0/en/charset-unicode-utf8mb3.html

  aa - schema's default character set: utf8
--More--ERROR: 2 errors were found. Please correct these issues before upgrading to avoid compatibility issues.
  cktest - schema's default character set: utf8
  drc - schema's default character set: utf8
  hcytest - schema's default character set: utf8
  percona - schema's default character set: utf8
  test - schema's default character set: utf8
  test1 - schema's default character set: utf8
  test2 - schema's default character set: utf8
  percona.checksums.db - column's default character set: utf8
  percona.checksums.tbl - column's default character set: utf8
  percona.checksums.chunk_index - column's default character set: utf8
  percona.checksums.lower_boundary - column's default character set: utf8
  percona.checksums.upper_boundary - column's default character set: utf8
  percona.checksums.this_crc - column's default character set: utf8
  percona.checksums.master_crc - column's default character set: utf8
  test.encrypted_data.salt - column's default character set: utf8
  test.products.product_name - column's default character set: utf8
  test.s.name - column's default character set: utf8
  test.sbtest1.c - column's default character set: utf8
  test.sbtest1.pad - column's default character set: utf8
  test.scores.student_name - column's default character set: utf8
  test.student.name - column's default character set: utf8
  test.student.course_ids - column's default character set: utf8
  test.students.name - column's default character set: utf8
  test.t1.info - column's default character set: utf8
  test.t2.name - column's default character set: utf8
  test.t2.address - column's default character set: utf8
  test.t8.address - column's default character set: utf8
  test.t9.name - column's default character set: utf8
  test.t9.city - column's default character set: utf8
  test.test_json.name - column's default character set: utf8
  test.test_no_pk.name - column's default character set: utf8
  test.user.name - column's default character set: utf8
  test2.A.name - column's default character set: utf8
  test2.t1.name - column's default character set: utf8
  test2.users.username - column's default character set: utf8
  test2.users.email - column's default character set: utf8

5) Table names in the mysql schema conflicting with new tables in 8.0
  No issues found

6) Partitioned tables using engines with non native partitioning
  No issues found

7) Foreign key constraint names longer than 64 characters
  No issues found

8) Usage of obsolete MAXDB sql_mode flag
  No issues found

9) Usage of obsolete sql_mode flags
  Notice: The following DB objects have obsolete options persisted for
    sql_mode, which will be cleared during upgrade to 8.0.
  More information:
    https://dev.mysql.com/doc/refman/8.0/en/mysql-nutshell.html#mysql-nutshell-removals

  test.insert_10000_records - PROCEDURE uses obsolete NO_AUTO_CREATE_USER
    sql_mode
  test.set_safe_updates_if_needed - PROCEDURE uses obsolete NO_AUTO_CREATE_USER
    sql_mode
  test.cleanup_expired_data - EVENT uses obsolete NO_AUTO_CREATE_USER sql_mode
  test2.trg_after_insert_A - TRIGGER uses obsolete NO_AUTO_CREATE_USER sql_mode
  test2.before_user_update - TRIGGER uses obsolete NO_AUTO_CREATE_USER sql_mode
  global system variable sql_mode - defined using obsolete NO_AUTO_CREATE_USER
    option

10) ENUM/SET column definitions containing elements longer than 255 characters
  No issues found

11) Usage of partitioned tables in shared tablespaces
  No issues found

12) Circular directory references in tablespace data file paths
  No issues found

13) Usage of removed functions
  No issues found

14) Usage of removed GROUP BY ASC/DESC syntax
  No issues found

15) Removed system variables for error logging to the system log configuration
  No issues found

16) Removed system variables
  No issues found

17) System variables with new default values
  Warning: Following system variables that are not defined in your
    configuration file will have new default values. Please review if you rely on
    their current values and if so define them before performing upgrade.
  More information:
    https://mysqlserverteam.com/new-defaults-in-mysql-8-0/

  back_log - default value will change
  collation_server - default value will change from latin1_swedish_ci to
    utf8mb4_0900_ai_ci
  event_scheduler - default value will change from OFF to ON
  explicit_defaults_for_timestamp - default value will change from OFF to ON
  innodb_autoinc_lock_mode - default value will change from 1 (consecutive) to
    2 (interleaved)
  innodb_flush_method - default value will change from NULL to fsync (Unix),
    unbuffered (Windows)
  innodb_flush_neighbors - default value will change from 1 (enable) to 0
    (disable)
  innodb_max_dirty_pages_pct - default value will change from 75 (%)  90 (%)
  innodb_max_dirty_pages_pct_lwm - default value will change from_0 (%) to 10
    (%)
  innodb_undo_log_truncate - default value will change from OFF to ON
  innodb_undo_tablespaces - default value will change from 0 to 2
  log_error_verbosity - default value will change from 3 (Notes) to 2 (Warning)
  max_allowed_packet - default value will change from 4194304 (4MB) to 67108864
    (64MB)
  max_error_count - default value will change from 64 to 1024
  optimizer_trace_max_mem_size - default value will change from 16KB to 1MB
  performance_schema_consumer_events_transactions_current - default value will
    change from OFF to ON
  performance_schema_consumer_events_transactions_history - default value will
    change from OFF to ON
  slave_rows_search_algorithms - default value will change from 'INDEX_SCAN,
    TABLE_SCAN' to 'INDEX_SCAN, HASH_SCAN'
  table_open_cache - default value will change from 2000 to 4000
  transaction_write_set_extraction - default value will change from OFF to
    XXHASH64

18) Zero Date, Datetime, and Timestamp values
  No issues found

19) Schema inconsistencies resulting from file removal or corruption
  Error: Following tables show signs that either table datadir directory or frm
    file was removed/corrupted. Please check server logs, examine datadir to
    detect the issue and fix it before upgrade

  test.#sql-157ae_c - present in INFORMATION_SCHEMA's INNODB_SYS_TABLES table
    but missing from TABLES table
  test.#sql-865c_3 - present in INFORMATION_SCHEMA's INNODB_SYS_TABLES table
    but missing from TABLES table

20) Tables recognized by InnoDB that belong to a different engine
  No issues found

21) Issues reported by 'check table x for upgrade' command
  No issues found

22) New default authentication plugin considerations
  Warning: The new default authentication plugin 'caching_sha2_password' offers
    more secure password hashing than previously used 'mysql_native_password'
    (and consequent improved client connection authentication). However, it also
    has compatibility implications that may affect existing MySQL installations. 
    If your MySQL installation must serve pre-8.0 clients and you encounter
    compatibility issues after upgrading, the simplest way to address those
    issues is to reconfigure the server to revert to the previous default
    authentication plugin (mysql_native_password). For example, use these lines
    in the server option file:
    
    [mysqld]
    default_authentication_plugin=mysql_native_password
    
    However, the setting should be viewed as temporary, not as a long term or
    permanent solution, because it causes new accounts created with the setting
    in effect to forego the improved authentication security.
    If you are using replication please take time to understand how the
    authentication plugin changes may impact you.
  More information:
    https://dev.mysql.com/doc/refman/8.0/en/upgrading-from-previous-series.html#upgrade-caching-sha2-password-compatibility-issues
    https://dev.mysql.com/doc/refman/8.0/en/upgrading-from-previous-series.html#upgrade-caching-sha2-password-replication

23) Columns which cannot have default values
  No issues found

24) Check for invalid table names and schema names used in 5.7
  No issues found

25) Check for orphaned routines in 5.7
  No issues found

26) Check for deprecated usage of single dollar signs in object names
  No issues found

27) Check for indexes that are too large to work on higher versions of MySQL
Server than 5.7
  No issues found

28) Check for deprecated '.<table>' syntax used in routines.
  No issues found

29) Check for columns that have foreign keys pointing to tables from a diffrent
database engine.
  No issues found

Errors:   2
Warnings: 59
Notices:  6