Oracle: Bulk Collect performance

Question

Can you help me to understand this phrase?

Without the bulk bind, PL/SQL sends a SQL statement to the SQL engine for each record that is inserted, u

Answer 1

AS I understand this, there are two engine involved, PL/SQL engine and SQL Engine. Executing a query that make use of one engine at a time is more efficient than switching between the two

Example:

  INSERT INTO t VALUES(1)

is processed by SQL engine while

  FOR Lcntr IN 1..20

  END LOOP

is executed by PL/SQL engine

If you combine the two statement above, putting INSERT in the loop,

FOR Lcntr IN 1..20
  INSERT INTO t VALUES(1)
END LOOP

Oracle will be switching between the two engines, for the each (20) iterations. In this case BULK INSERT is recommended which makes use of PL/SQL engine all through the execution