The SQL runtime warning output facility can be used for the following purposes:

• To detect in advance the possibility of a PDCWAITTIME timeout occurring for a UAP whose response time to HiRDB server processes has increased, due to an increase in the volume of data
• To collect for use as tuning data information on SQL code whose response wait time meets or exceeds a specific value

The amount of time on the basis of which warning information is to be output is called the elapsed time basis for output of warning information. When SQL execution time exceeds the elapsed time basis for output of warning information, warning information is output. The elapsed time basis for output of warning information is determined as either of the following:

• A percentage of the value specified in the PDCWAITTIME operand
• An elapsed time trigger for output of a warning to a file; you can specify a very precise output trigger time value (in milliseconds, for example).

The SQL runtime warning output facility monitors all SQL statements except for CONNECT statements.

When information warning that a PDCWAITTIME timeout might occur is output, you should take the following actions based on the output information:

1. Determine if lockout has occurred.
2. Determine if a network failure has occurred.
3. Tune the SQL code.
4. Increase the value specified in the PDCWAITTIME operand.
5. Check if the execution time of the SQL code has increased because of an increase in the number of data transactions.

When the SQL runtime warning output facility is being used, warning information might be output, even when the execution time of SQL code is less than the set time. Warning information (message only) might also be output, even when the SQL runtime warning output facility is not being used. The following table describes the conditions under which warning information is output by the SQL runtime warning output facility.

Table 8-9 Conditions under which warning information is output by the SQL runtime warning output facility

Condition		Warning information that is output
		SQL runtime warning information file	KFPA20009-W message
When the SQL runtime warning output facility is being used	The SQL execution time meets or exceeds the set time.	Yes	Yes
	Server process is terminated forcibly due to a PDCWAITTIME timeout.	Part	Part
	Server process is terminated forcibly for some other reason.	Part	Part
When the SQL runtime warning output facility is not being used	The SQL execution time meets or exceeds the set time.	No	No
	Server process is terminated forcibly due to a PDCWAITTIME timeout.	No	Part
	Server process is terminated forcibly for some other reason.	No	Part

Legend:

Yes: The indicated information is output.

Part: The indicated information is partially output.

In addition, the SQL runtime warning information file or the KFPA20009-W message might not be output depending on the timing of the forced termination.

Note, also, that you can suppress re-output of the SQL runtime information file and the KFPA20009-W message with the pd_dump_suppress_watch_time operand.

No: The indicated information is not output.

Note

When SQL execution time exceeds the value in the PDCWAITTIME operand, the server process is terminated forcibly regardless of whether the SQL runtime warning output facility is being used.

The following figures illustrate the relationship between PDCWAITTIME and the SQL runtime warning output facility.

Figure 8-14 Relationship between PDCWAITTIME and the SQL runtime warning output facility (1 of 2)

Figure 8-15 Relationship between PDCWAITTIME and the SQL runtime warning output facility (2 of 2)

Explanation

• The range of measuring SQL execution time is from the time a request sent from a client is received by the server until the execution result in response to the request is returned.
• When the SQL execution result is returned to the client, HiRDB determines the SQL execution time. If the SQL execution time equals or exceeds the set time, the warning information is output.