Changes in MySQL 8.0 Please see the documentation for further information. If you encounter this error when upgrading to MySQL 8.0.17, perform the following workaround: 1. Restart the server with  --upgrade=force  to force the upgrade operation to proceed. 2. Identify partitioned table file names with lowercase partition name delimiters  (#p#  or  #sp# ): 3. For each file identified, rename the associated table using a temporary name, then rename the table back to its original name. 4. Verify that there are no partitioned table file names lowercase partition name delimiters (an empty result set should be returned). mysql> RENAME TABLE  table_name  TO  temporary_table_name ; mysql> RENAME TABLE  temporary_table_name  TO  table_name ; mysql> Because of the regression still present in the MySQL 8.0.14, 8.0.15, and 8.0.16 releases, importing partitioned tables from MySQL 8.0.14, 8.0.15, or 8.0.16 to MySQL 8.0.17 is not supported on case- sensitive file systems where  lower_case_table_names=1 . Attempting to do so results in a “Tablespace is missing for table”  error. 5. Run  ANALYZE TABLE  on each renamed table to update the optimizer statistics in the mysql.innodb_index_stats  and  mysql.innodb_table_stats  tables. •MySQL uses delimiter strings when constructing tablespace names and file names for table partitions. A “  #p#  ”  delimiter string precedes partition names, and an “  #sp#  ”  delimiter string precedes subpartition names, as shown: mysql>  SELECT Empty set (0.00 sec) Additionally, partition tablespace names and file names generated based on user-specified partition or subpartition names, which can be specified in uppercase or lowercase, are now generated (and stored internally) in lowercase regardless of the  lower_case_table_names  setting to ensure case- insensitivity. For example, if a table partition is created with the name  PART_1 , the tablespace name and file name are generated in lowercase: Historically, delimiter strings have been uppercase ( #P#  and  #SP# ) on case-sensitive file systems such as Linux, and lowercase ( #p#  and  #sp# ) on case-insensitive file systems such as Windows. As of MySQL 8.0.19, delimiter strings are lowercase on all file systems. This change prevents issues when migrating data directories between case-sensitive and case-insensitive file systems. Uppercase delimiter strings are no longer used. During upgrade, MySQL checks and modifies if necessary: •Partition file names on disk and in the data dictionary to ensure lowercase delimiters and partition names. •Partition metadata in the data dictionary for related issues introduced by previous bug fixes. 276 schema_name . table_name #p# part_1 table_name #p# part_1 .ibd schema_name . table_name #p# partition_name #sp# subpartition_name table_name #p# partition_name #sp# subpartition_name .ibd