Derby Reference Manual

SYSXPLAIN_STATEMENT_TIMINGS system table

This table captures information about statement timings which occurred during statements that were executed using RUNTIMESTATISTICS with XPLAIN style (see the RUNTIMESTATISTICS section in the Derby Reference Manual for more information on how to configure this). Note in particular that you must call syscs_util.syscs_set_statistics_timing(1) to enable timing information to be captured. Rows in this table are typically joined with rows in SYSXPLAIN_STATEMENTS and SYSXPLAIN_RESULTSETS during analysis. For example:

        select s.stmt_text, st.execute_time
        from my_stats.sysxplain_statements s,
             my_stats.sysxplain_statement_timings st
        where s.timing_id = st.timing_id
        order by st.execute_time desc

Rows in this table are added automatically when Derby has been configured appropriately. The rows remain in the table until you delete them or drop the table.

See "Working with RunTimeStatistics" in the Tuning Derby for additional information.

Column Name	Type	Length	Nullability	Contents
TIMING_ID	CHAR	36	false	A unique identifier for this particular row. This column can be used to join with the TIMING_ID column in SYSXPLAIN_STATEMENTS to match statement timings with their corresponding statements.
PARSE_TIME	BIGINT		false	The time in milliseconds that Derby took to parse this statement.
BIND_TIME	BIGINT		false	The time in milliseconds that Derby took to bind this statement. Binding a statement is the process of resolving table and column references in the statement against the table and column definitions in the system catalogs.
OPTIMIZE_TIME	BIGINT		false	The time in milliseconds that Derby took to optimize this statement. During optimization, Derby considers the various possible execution plans that could be used for the statement, and chooses the one it thinks will be best.
GENERATE_TIME	BIGINT		false	The time in milliseconds that Derby took to generate code for this statement.
COMPILE_TIME	BIGINT		false	The time in milliseconds that Derby took to compile this statement. Overall statement time is divided into compile time and execute time, and the compile time is further sub-divided into parse, bind, optimize, and generate time.
EXECUTE_TIME	BIGINT		false	The time in milliseconds that Derby took to execute this statement.
BEGIN_COMP_TIME	TIMESTAMP		false	The time at which Derby began to compile this statement.
END_COMP_TIME	TIMESTAMP		false	The time at which Derby finished compiling this statement.
BEGIN_EXE_TIME	TIMESTAMP		false	The time at which Derby began to execute this statement.
END_EXE_TIME	TIMESTAMP		false	The time at which Derby finished executing this statement.

Java DB

Apache Derby

SYSXPLAIN_STATEMENT_TIMINGS system table