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1.

What are the four main query processing components in PostgreSQL?

Parser, Planner, Executor, Rewriter.

Lexer, scan, Parser, Executor.

Cost estimator, Parser, Executor, Rewriter.

2.

What is the result of running the following statement? EXPLAIN ANALYZE INSERT INTO animal (ani_id, name, weight_kg, cat_id, enc_id) VALUES (28, 'Robin Robin', 0.5, 2, 4);

The statement isn't syntactically correct and will throw an error.

The query plan for the INSERT statement is displayed, but the new record statement will be rolled back and not inserted into the animal table.

The query plan for the INSERT statement is displayed, and a new record is inserted into the animal table.

3.

You're working on a complex query. You would like to see the query optimizer's plan to help you understand why it's running slowly. What should you do?

Add the keyword EXPLAIN before the query statement.

Add the keyword ANALYZE before the query statement.

Add the keywords EXPLAIN ANALYZE before the query statement.

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