SQL Reference

Appendix L. Explain Register Values

This appendix describes the interaction of the CURRENT EXPLAIN MODE and CURRENT EXPLAIN SNAPSHOT special register values with each other and with the PREP and BIND commands.

The CURRENT EXPLAIN MODE and CURRENT EXPLAIN SNAPSHOT special register values interact in the following way for dynamic SQL.

Table 108. Interaction of Explain Special Register Values for Dynamic SQL

EXPLAIN MODE values	EXPLAIN SNAPSHOT values
	NO	YES	EXPLAIN
NO	Results of query returned.	Explain tables populated Results of query returned.	Explain tables populated. Results of query not returned (Dynamic statements not executed).
YES	Explain Snapshot taken. Results of query returned.	Explain tables populated Explain Snapshot taken Results of query returned.	Explain tables populated Explain Snapshot taken Results of query not returned (Dynamic statements not executed).
EXPLAIN	Explain Snapshot taken Results of query not returned (Dynamic statements not executed).	Explain tables populated Explain Snapshot taken Results of query not returned (Dynamic statements not executed).	Explain tables populated Explain Snapshot taken Results of query not returned (Dynamic statements not executed).

The CURRENT EXPLAIN MODE special register interacts with the EXPLAIN bind option in the following way for dynamic SQL.

Table 109. Interaction of EXPLAIN Bind Option and CURRENT EXPLAIN MODE

EXPLAIN Bind option values	EXPLAIN MODE values
	NO	YES	ALL
NO	Results of query returned.	Explain tables populated for static SQL Results of query returned.	Explain tables populated for static SQL Explain tables populated for dynamic SQL Results of query returned.
YES	Explain tables populated for dynamic SQL Results of query returned.	Explain tables populated for static SQL Explain tables populated for dynamic SQL Results of query returned.	Explain tables populated for static SQL Explain tables populated for dynamic SQL Results of query returned.
EXPLAIN	Explain tables populated for dynamic SQL Results of query not returned (Dynamic statements not executed).	Explain tables populated for static SQL Explain tables populated for dynamic SQL Results of query not returned (Dynamic statements not executed).	Explain tables populated for static SQL Explain tables populated for dynamic SQL Results of query not returned (Dynamic statements not executed).

The CURRENT EXPLAIN SNAPSHOT special register interacts with the EXPLSNAP bind option in the following way for dynamic SQL.

Table 110. Interaction of EXPLSNAP bind Option and CURRENT EXPLAIN SNAPSHOT

EXPLSNAP Bind option values	EXPLAIN SNAPSHOT values
	NO	YES	ALL
NO	Results of query returned.	Explain Snapshot taken for static SQL Results of query returned.	Explain Snapshot taken for static SQL Explain Snapshot taken for dynamic SQL Results of query returned.
YES	Explain Snapshot taken for dynamic SQL Results of query returned.	Explain Snapshot taken for static SQL Explain Snapshot taken for dynamic SQL Results of query returned.	Explain Snapshot taken for static SQL Explain Snapshot taken for dynamic SQL Results of query returned.
EXPLAIN	Explain Snapshot taken for dynamic SQL Results of query not returned (Dynamic statements not executed).	Explain Snapshot taken for static SQL Explain Snapshot taken for dynamic SQL Results of query not returned (Dynamic statements not executed).	Explain Snapshot taken for static SQL Explain Snapshot taken for dynamic SQL Results of query not returned (Dynamic statements not executed).

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