Performance Schema Connection Tables startup. To set the table size explicitly, set the  performance_schema_accounts_size  system variable at server startup. To disable account statistics, set this variable to 0. The  accounts  table has the following columns. For a description of how the Performance Schema maintains rows in this table, including the effect of  TRUNCATE TABLE , see Section 27.12.8, “Performance Schema Connection Tables” . The client user name for the connection. This is  NULL  for an internal thread, or for a user session that failed to authenticate. • USER • HOST • CURRENT_CONNECTIONS • TOTAL_CONNECTIONS •Primary key on ( USER ,  HOST ) The total number of connections for the account. The  accounts  table has these indexes: The current number of connections for the account. The host from which the client connected. This is  NULL  for an internal thread, or for a user session that failed to authenticate. The  hosts  table contains a row for each host from which clients have connected to the MySQL server. For each host name, the table counts the current and total number of connections. The table size is autosized at server startup. To set the table size explicitly, set the  performance_schema_hosts_size  system variable at server startup. To disable host statistics, set this variable to 0. The  hosts  table has the following columns. For a description of how the Performance Schema maintains rows in this table, including the effect of  TRUNCATE TABLE , see Section 27.12.8, “Performance Schema Connection Tables” . 27.12.8.2 The hosts Table • HOST • CURRENT_CONNECTIONS • TOTAL_CONNECTIONS •Primary key on ( HOST ) 4991 27.12.8.3 The users Table The  hosts  table has these indexes: The total number of connections for the host. The current number of connections for the host. The host from which the client connected. This is  NULL  for an internal thread, or for a user session that failed to authenticate.