How To Calculate Expressions with SQL Statements

Q

How To Calculate Expressions with SQL Statements? - MySQL FAQs - Introduction to SQL Basics

✍: FYIcenter.com

A

There is no special SQL statements to calculate expressions. But you can use the "SELECT expression FROM DUAL" statement return the calculated value of an expression. "DUAL" is a dummy table in the server. The tutorial exercise below shows you some good examples:

SELECT 'Hello world!' FROM DUAL; 
   Hello world!

SELECT (1+2)*3/4 FROM DUAL;
   2.2500

SELECT TRUE FROM DUAL;
   1

SELECT TRUE AND FALSE FROM DUAL;
   0

SELECT TIME(SYSDATE()) FROM DUAL;
   21:30:26

2016-11-09, 9448👍, 1💬

How To Calculate Expressions with SQL Statements
How To Calculate Expressions with SQL Statements? - MySQL FAQs - Introduction to SQL Basics There is no special SQL statements to calculate expressions. But you can use the "SELECT expression FROM DUAL" statement return the calculated value of an expression. "DUAL" is a dummy table in the server. Th... 2016-11-09, 9449👍, 1💬

💬 2016-11-09 lux: good

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