PL/SQL Optimizer and Performance Tuning
16 Questions
2 Views

Choose a study mode

Play Quiz
Study Flashcards
Spaced Repetition
Chat to lesson

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

What can be done if the overhead of the PL/SQL optimizer makes compilation of very large applications too slow?

  • Set the compilation parameter PLSQL_OPTIMIZE_LEVEL=3
  • Disable the PL/SQL optimizer
  • Set the compilation parameter PLSQL_OPTIMIZE_LEVEL=1 (correct)
  • Enable the PL/SQL optimizer at a higher level
  • When is dynamic SQL useful in PL/SQL programs?

  • When avoiding any run-time generation of SQL statements
  • When knowing at compile time the full text of a SQL statement
  • When writing fixed SQL statements
  • When knowing at compile time the number and data types of input and output variables of a dynamic SQL statement (correct)
  • What is the most common cause of slowness in PL/SQL programs?

  • Using appropriate indexes
  • Inefficient use of bulk SQL
  • Slow SQL statements (correct)
  • Query hints in SQL statements
  • What is native dynamic SQL?

    <p>A methodology for generating and running SQL statements at run time</p> Signup and view all the answers

    How can you minimize the performance overhead of communication between PL/SQL and SQL?

    <p>Use set of PL/SQL features known as bulk SQL</p> Signup and view all the answers

    In what cases is dynamic SQL particularly useful?

    <p>When writing general-purpose and flexible programs like ad hoc query systems</p> Signup and view all the answers

    What is the purpose of tuning loops in PL/SQL applications?

    <p>To optimize the loops themselves and the code inside them</p> Signup and view all the answers

    Why should functions not be invoked unnecessarily in queries?

    <p>To make the invocation as efficient as possible</p> Signup and view all the answers

    What is the advantage of using data types like PLS_INTEGER, BINARY_FLOAT, and BINARY_DOUBLE?

    <p>They use hardware arithmetic for better performance</p> Signup and view all the answers

    What does the FORALL statement in PL/SQL do?

    <p>Sends DML statements from PL/SQL to SQL in batches rather than one at a time</p> Signup and view all the answers

    What is the purpose of bulk SQL in PL/SQL?

    <p>To minimize the performance overhead of communication between PL/SQL and SQL</p> Signup and view all the answers

    Why should one avoid using data types in the NUMBER family?

    <p>To use hardware arithmetic for better performance</p> Signup and view all the answers

    How can short-circuit evaluation be utilized in logical expressions in PL/SQL?

    <p>By putting least expensive conditional tests first in logical expressions</p> Signup and view all the answers

    What is bulk binding in bulk SQL?

    <p>It binds an entire collection of values at once</p> Signup and view all the answers

    What are obstacles to scaling up RDBMS as mentioned in the text?

    <p>Scaling Relational Databases Is Hard because todays business is digital.</p> Signup and view all the answers

    What is an important consideration when using conditional expressions in PL/SQL?

    <p>Put least expensive conditional tests first to take advantage of short-circuit evaluation.</p> Signup and view all the answers

    More Like This

    PL/SQL Triggers Quiz
    5 questions
    PL/SQL Quiz
    5 questions

    PL/SQL Quiz

    ThriftyErudition avatar
    ThriftyErudition
    PL/SQL Composite Data Types Quiz
    10 questions
    Exception Handling in PL/SQL
    8 questions
    Use Quizgecko on...
    Browser
    Browser