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The following is a list of all search strategies that are avaible to the SQL optimizer. The names match the return codes of the EXPLAIN statement. You can use the EXPLAIN statement to find out which search strategy the SQL optimizer uses for an SQL statement.

SQL Optimizer Search Strategies

CATALOG ACCESS USING USERS TABLE LIST

CATALOG KEY ACCESS

CATALOG SCAN

CATALOG SCAN USING USER EQUAL CONDITION

DIFFERENT STRATEGIES FOR OR-TERMS

EQUAL CONDITION FOR INDEX

EQUAL CONDITION FOR KEY

IN CONDITION FOR INDEX

IN CONDITION FOR KEY

INDEX SCAN

JOIN VIA INDEXED COLUMN

JOIN VIA KEY COLUMN

JOIN VIA KEY RANGE

JOIN VIA MULTIPLE INDEXED COLUMNS

JOIN VIA MULTIPLE KEY COLUMNS

JOIN VIA RANGE OF MULTIPLE INDEXED COLUMNS

JOIN VIA RANGE OF MULTIPLE KEY COLUMNS

NO RESULT SET POSSIBLE

NO STRATEGY NOW (ONLY AT EXECUTION TIME)

RANGE CONDITION FOR KEY

RANGE CONDITION FOR INDEX

SUBQ CONDITION FOR INDEX

SUBQ CONDITION FOR KEY

TABLE SCAN

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