Which utility should be used to obtain the access paths details?
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QUIESCE
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EXPLAIN
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REORG
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RUNSTATS
To answer this question, the user needs to have a basic understanding of database management systems and utilities used to manage databases.
QUIESCE is a utility used to temporarily halt the activity on the database, allowing for maintenance operations to take place. It is not used to obtain access path details.
EXPLAIN is a utility used to display the access path details for a particular SQL statement. This option is correct.
REORG is a utility used to reorganize the physical storage of a database table, and is not used to obtain access path details.
RUNSTATS is a utility used to collect statistical information about the data contained in a database table, and is not used to obtain access path details.
Therefore, the correct answer is:
The Answer is: B. EXPLAIN
Correct answer: EXPLAIN. In DB2, the EXPLAIN facility captures the access path chosen by the optimizer for a SQL statement (index vs. table-space scan, join method, sort steps, etc.) into the PLAN_TABLE (and related tables) at bind/prepare time. QUIESCE suspends access to an object for utility processing; REORG physically reorganizes data/indexes to remove disorganization; RUNSTATS collects statistics that feed the optimizer's decisions but does not itself report the chosen access path. Only EXPLAIN produces the access-path detail.