MySQL 5.7 Reference Manual Including MySQL NDB Cluster 7.5 and NDB Cluster 7.6
These views summarize overall statement statistics, grouped by host. By default, rows are sorted by descending total latency.
The
host_summary_by_statement_latency
and
x$host_summary_by_statement_latency
views have these columns:
host
The host from which the client connected. Rows for which
the HOST column in the underlying
Performance Schema table is NULL are
assumed to be for background threads and are reported with
a host name of background.
total
The total number of statements for the host.
total_latency
The total wait time of timed statements for the host.
max_latency
The maximum single wait time of timed statements for the host.
lock_latency
The total time waiting for locks by timed statements for the host.
rows_sent
The total number of rows returned by statements for the host.
rows_examined
The total number of rows read from storage engines by statements for the host.
rows_affected
The total number of rows affected by statements for the host.
full_scans
The total number of full table scans by statements for the host.