How to use SQL Tuning Advisor in Oracle SQL Developer?

Oracle SQL Developer -> Connections -> Right mouse click on desired database connection name (e.g. XE) -> Click "Open SQL Worksheet" -> Input and select SQL code block -> Right mouse click then select "SQL Tuning Advisor" or press "CTRL+F12" -> Lastly, analyze the result.

How to take screenshot on top window quickly?

e.g.
Alt key + Print Screen key -> Then CTRL + V in "mspaint.exe" -> Save it.

How to see both Oracle VM Virtual Box 32bit/64bit options?

e.g. If there are only 32 bit Linux distro in the OS list, you should enable virtualization support in BIOS

* BIOS -> CMOS Setup Utility -> Virtualization Technology -> [Enabled]

e.g. bulk insert

SET TIMING ON
/
CREATE TABLE HR.EMPLOYEES_TEST
AS
   SELECT *
     FROM HR.EMPLOYEES
    WHERE ROWNUM < 0;
/
DECLARE
   TYPE TABLE_TYP IS TABLE OF HR.EMPLOYEES%ROWTYPE;

   TABLE_ROWS   TABLE_TYP := TABLE_TYP ();

   CURSOR TEST_CURSOR
   IS
      SELECT * FROM HR.EMPLOYEES;

   V_COUNT      NUMBER;
BEGIN
   SELECT COUNT (1) INTO V_COUNT FROM HR.EMPLOYEES;

   DBMS_OUTPUT.PUT_LINE ('TOTAL NUMBER OF ROWS: ' || V_COUNT);

   OPEN TEST_CURSOR;

   LOOP
      FETCH TEST_CURSOR BULK COLLECT INTO TABLE_ROWS LIMIT 10;

      FORALL A IN TABLE_ROWS.FIRST .. TABLE_ROWS.LAST
         INSERT INTO HR.EMPLOYEES_TEST
              VALUES TABLE_ROWS (A);

      COMMIT;
      DBMS_OUTPUT.PUT_LINE (
         'Looping, TEST_CURSOR%rowcount = ' || TEST_CURSOR%ROWCOUNT);
      EXIT WHEN TEST_CURSOR%NOTFOUND;
   
   --EXIT WHEN TEST_CURSOR%ROWCOUNT > 1000000;

   END LOOP;

   DBMS_OUTPUT.PUT_LINE (
      'Exited, TEST_CURSOR%rowcount = ' || TEST_CURSOR%ROWCOUNT);

   CLOSE TEST_CURSOR;
END;
/

[ADVICE] Free Database Monitoring Tool

You may use following free tool instead of Oracle EM (Enterprise Manager)

• ASH Viewer (Active Session History)

Naming conventions for database objects

index -> [SHORT_TABLE_NAME]_[SHORT_COLUMN_NAME]_[INDEX_TYPE]
e.g. EMP_DEPARTMENT_IX

constraint -> [SHORT_TABLE_NAME]_[SHORT_COLUMN_NAME]_[CONSTRAINT_TYPE]
e.g. 
NOT NULL const. -> EMP_EMAIL_NN
FOREIGN KEY (Referential Integrity) const. 
Source table: EMPLOYEES
Column name of source table: DEPARTMENT_ID
-> EMP_DEPT_FK

trigger -> [TABLE_NAME]_TRG
e.g. HR.EMPLOYEES_TRG

sequence -> [TABLE_NAME]_SEQ
e.g. HR.EMPLOYEES_SEQ

type -> [TABLE_NAME]_TYP
e.g. HR.EMPLOYEES_TYP

How to debug code in Toad?

e.g.
Toad for Oracle -> Database -> Schema Browser -> Click HR -> Click Procedures -> Double click to "PROC_EXEC" procedure -> Set breakpoint or Add Watch (optional) -> Press Shift+F7 or Click Debug-Trace Into -> Confirm -> Click Execute

How to grap and drop table columns in Toad?

e.g.
Toad for Oracle -> Type HR.EMPLOYEES then Press F4 in Editor -> Select desired columns by CTRL key-> Drag and drop to Editor by mouse -> Columns should show in Editor