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sqlplus - How can I see the SQL execution plan in Oracle?

I'm learning about database indexes right now, and I'm trying to understand the efficiency of using them.

  • I'd like to see whether a specific query uses an index.
  • I want to actually see the difference between executing the query using an index and without using the index (so I want to see the execution plan for my query).

I am using sql+.

How do I see the execution plan and where can I found in it the information telling me whether my index was used or not?

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Try using this code to first explain and then see the plan:

Explain the plan:

explain plan 
for 
select * from table_name where ...;

See the plan:

select * from table(dbms_xplan.display);

Edit: Removed the brackets


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