MySQL 8.0 Reference Manual Including MySQL NDB Cluster 8.0

13.1.20.2 Files Created by CREATE TABLE

For an InnoDB table created in a file-per-table tablespace or general tablespace, table data and associated indexes are stored in a .ibd file in the database directory. When an InnoDB table is created in the system tablespace, table data and indexes are stored in the ibdata* files that represent the system tablespace. The innodb_file_per_table option controls whether tables are created in file-per-table tablespaces or the system tablespace, by default. The TABLESPACE option can be used to place a table in a file-per-table tablespace, general tablespace, or the system tablespace, regardless of the innodb_file_per_table setting.

For MyISAM tables, the storage engine creates data and index files. Thus, for each MyISAM table tbl_name, there are two disk files.

File Purpose
tbl_name.MYD Data file
tbl_name.MYI Index file

Chapter 16, Alternative Storage Engines, describes what files each storage engine creates to represent tables. If a table name contains special characters, the names for the table files contain encoded versions of those characters as described in Section 9.2.4, “Mapping of Identifiers to File Names”.