Click on an individual query to see more detailed information about the individual query in a pop-up window, as shown in Figure 23.2, “MySQL Enterprise Monitor User Interface: Canonical Query Tab for a Query”. The available tabs within this window depend on whether you have configured the more detailed query information. By default, you see the Canonical Query view.
You can also view Example Query, which
provides more detailed data about a specific query, including the
data and parameters submitted. You can also enable
Explain Query, which lets you remotely
EXPLAIN statement with the specified
query and view the resulting information. Finally, you can view
any graph data produced during the execution of the query by using
the Graphs tab.
The Canonical Query tab:
The canonical view for a query provides three different views
of the query, which can be changed using the links under the
Canonical Form section. The
truncated version is a shortened version of
the query. The
full version of the query is
the entire query statement. Normalization removes the
constants from the individual queries so that queries
following the same logical structure are identified as the
same basic query.
The "full" version of statements provided by the digested Performance Schema may be truncated, as the Performance Schema statement digest may truncate the statement due to memory constraints.
In addition to the summary information given in the table, the Execution Time Statistics section provides you with more detailed execution time statistics, including the minimum time, maximum time, average time, total time and the standard deviation. The standard deviation lets you determine whether a particular invocation of a query is outside the normal distribution of times for the given query.
The Row Statistics provide more detailed contents on the maximum, minimum, average, total, and standard deviation for the number of rows returned by the query, and the total size and maximum size of the data returned. The time period for the total and average figures is shown under the Time Span header.
The Execution Summary section provides the summary data available in the main table, covering the execution count, and counts of the number of errors, warnings, queries that triggered table scans, and those that indicated a bad index use.
The First Seen reports when the normalized version of this query was first seen, whether or not this was within the indicated Time Span.
To close the query detail window, click the Hide button.
The Example Query tab:
The Example Query tab provides detailed information about the most expensive query executed, as determined by the execution time.
In addition to the full query, with data, that was executed, the tab shows the execution time, data, user, thread ID, client host and execution host for the given query.
For queries from any of the MySQL Enterprise Plugin for Connectors, the Source Location contains the information from the Connector where the query was generated.
The Explain Query tab:
The Explain Query tab lets you view the
output from running the query with the
EXPLAIN prefix. For more information, see
Explains are generated for query data supplied by the MySQL Enterprise Monitor Proxy and Aggregator, Connector/J plugin, and Performance Schema sources.
Explain is supported for all DML statements on MySQL 5.6.3
or higher. On earlier versions, only
SELECT is supported.
If the Query Analyzer is used with the MySQL Enterprise Monitor Proxy and Aggregator, EXPLAIN is not performed for any SELECT statement which uses SQL_CALC_FOUND_ROWS.
The Graphs tab:
The Graphs tab shows key graphs over the selected time period for the example query. Shown are graphs of the Execution Time, Executions, Rows, and Kilobytes. These can be used to identify deviations from the normal values. Unlike the query-correlation graphs, these graphs shown only the query statistics over the given time period.