Examine the following parameter values for a session:
PLSQL_CODE_TYPE = NATIVE
PLSQL_OPTIMIZE_LEVEL = 2
Which two statements are true in this scenario? (Choose two.)
A.
The compiler automatically inlines subprograms even if you specify that they not be inlined.
B.
The compiler optimizes PL/SQL programs by elimination of unnecessary computations and
exceptions.
C.
PL/SQL statements in a PL/SQL program unit are compiled into machine-readable code, and
stored in the SYSTEM tablespace.
D.
PL/SQL statements in a PL/SQL program unit are compiled into an intermediate form,
machine-readable code, which is stored in the database dictionary.
B, C
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http://docs.oracle.com/database/121/REFRN/refrn10253.htm#REFRN10253
http://docs.oracle.com/database/121/REFRN/refrn10255.htm#REFRN10255
B, C
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docs.oracle.com/database/121/REFRN/refrn10253.htm#REFRN10253
docs.oracle.com/database/121/REFRN/refrn10255.htm#REFRN10255
B , D
B , C
BC
B. true
PLSQL_OPTIMIZE_LEVEL Values
PLSQL_OPTIMIZE_LEVEL specifies the optimization level that will be used to compile
PL/SQL library units. The higher the setting of this parameter, the more effort the compiler
makes to optimize PL/SQL library units.
0: Maintains the evaluation order and hence the pattern of side effects, exceptions, and package
initializations of Oracle9i and earlier releases. Also removes the new semantic identity of
BINARY_INTEGER and PLS_INTEGER and restores the earlier rules for the evaluation of integer
expressions. Although code will run somewhat faster than it did in Oracle9i, use of level 0 will
forfeit most of the performance gains of PL/SQL in Oracle Database 10g.
1: Applies a wide range of optimizations to PL/SQL programs including the elimination of
unnecessary computations and exceptions, but generally does not move source code
out of its original source order.
2: Applies a wide range of modern optimization techniques beyond those of level 1 including
changes which may move source code relatively far from its original location.
3: Applies a wide range of optimization techniques beyond those of level 2, automatically
including techniques not specifically requested.
Generally, setting this parameter to 2 pays off in better execution performance.
If, however, the compiler runs slowly on a particular source module or if optimization
does not make sense for some reason (for example, during rapid turnaround development),
then setting this parameter to 1 will result in almost as good a compilation with less use of
compile-time resources.
http://docs.oracle.com/database/121/REFRN/GUID-364B752A-4335-468C-B4BA-AAC32D75385A.htm#REFRN10255
C. true
Compiling PL/SQL Units for Native Execution
You can usually speed up PL/SQL units by compiling them into native code
(processor-dependent system code), which is stored in the SYSTEM tablespace.
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