Author: Randy Sims

Reading Linux’s TOP Screen

The top command in Linux provides information about the top CPU processess and provides performance information. The processes displayed are sorted by CPU usage with the information updating by default every 3 seconds. Top also displays information about memory and CPU waiting for I/O. Below is a line-by-line explanation of the top screen. To find out … Continue reading Reading Linux’s TOP Screen

INTERVAL: Clock Math

INTERVAL is a function that provides a way to add, subtract or just convert. SELECT INTERVAL '300' MONTH, INTERVAL '54-2' YEAR TO MONTH, INTERVAL '11:12:10.1234567' HOUR FROM DUAL; Which is the correct output of the above query? A. +25-00, +54-02, +00 11:12:10.123457 B. +00-300, +54-02,+00 11:12:10.123457 C. +25-00,+00-650,+00 11:12:10.123457 D. +00-300,+00-650,+00 11:12:10.123457 ANSWER: A INTERVAL … Continue reading INTERVAL: Clock Math

Oracle Set Operators: UNION, INTERSECT and MINUS

Did you know you can do set-based math with Oracle? With the UNION, INTERSECT and MINUS set operators, you can compare one result set to another and add or subtract results, called a compound query. This can be a handy tool for your toolbox. First, a couple of things to keep in mind. The number of … Continue reading Oracle Set Operators: UNION, INTERSECT and MINUS

Ending a Transaction

QUESTION: Which three statements/commands would cause a transaction to end? (Choose three.) A. COMMIT B. SELECT C. CREATE D. ROLLBACK E. SAVEPOINT Answer: A,C,D A transaction is a unit of work containing SQL statements. Transactions end when they are committed or rolled back, or when a DDL statement is issued. COMMIT will make the changes … Continue reading Ending a Transaction

Transactions and SAVEPOINT

QUESTION: Which two statements describe the consequence of issuing the ROLLBACK TO SAVE POINT a command in the session? SQL> CREATE TABLE product 2 (pcode NUMBER(2), 3 pname VARCHAR2(10)); Table created. SQL> INSERT INTO product VALUES (1,'pen'); 1 row created. SQL> INSERT INTO product VALUES (2,'pencil'); 1 row created. SQL> SAVEPOINT a; Savepoint created. SQL> … Continue reading Transactions and SAVEPOINT

August 14, 1765 – Boston Meets the Sons of Liberty

On this day,  about five months following the signing of the Stamp Act of 1765, two hundred forty-four years ago, an effigy was hung from a tree on Newbury Street in Boston. The effigy was of Andrew Oliver, the man to be commissioned as the Distributor of Stamps for Massachusetts. Oliver was set up to be the … Continue reading August 14, 1765 – Boston Meets the Sons of Liberty