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, 8147👍, 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, 8148👍, 1💬

💬 2016-11-09 lux: good

How To Escape Special Characters in SQL statements
How To Escape Special Characters in SQL statements? - MySQL FAQs - Introduction to SQL Basics There are a number of special characters that needs to be escaped (protected), if you want to include them in a character string. Here are some basic character escaping rules: The escape character (\) needs... 2007-05-11, 7102👍, 0💬

How To Include Numeric Values in SQL statements
How To Include Numeric Values in SQL statements? - MySQL FAQs - Introduction to SQL Basics If you want to include a numeric value in your SQL statement, you can enter it directly as shown in the following examples: SELECT 255 FROM DUAL; -- An integer 255 SELECT -6.34 FROM DUAL; -- A regular number -... 2007-05-11, 5392👍, 0💬

How To Include Character Strings in SQL statements
How To Include Character Strings in SQL statements? - MySQL FAQs - Introduction to SQL Basics If you want to include character strings in your SQL statements, you need to quote them in one of the following formats: Using single quotes. For example 'FYIcenter.com'. Using double quotes. For example "F... 2007-05-11, 4991👍, 0💬

What Are Numeric Data Types
What Are Numeric Data Types? - MySQL FAQs - Introduction to SQL Basics MySQL supports the following numeric data types: BIT(n) - An integer with n bits. BOOL same as BOOLEAN - Boolean values stored in 1 bit. TINYINT - A small integer stored in 1 byte. SMALLINT - A small integer stored in 2 bytes. ME... 2007-05-11, 4884👍, 0💬

How To Include Comments in SQL Statements
How To Include Comments in SQL Statements? - MySQL FAQs - Introduction to SQL Basics If you want to include comments in a SQL statement, you can first enter "--", then enter your comment until the end of the line. The tutorial exercise below shows you some good examples: SELECT 'Hello world!' FROM D... 2007-05-11, 4835👍, 0💬

What Are the Differences between CHAR and VARCHAR
What Are the Differences between CHAR and VARCHAR? - MySQL FAQs - Introduction to SQL Basics CHAR and VARCHAR are both ASCII character data types by default. But they have the following major differences: CHAR stores values in fixed lengths. Values are padded with space characters to match the speci... 2007-05-11, 4830👍, 0💬

What Are the Differences between CHAR and NCHAR
What Are the Differences between CHAR and NCHAR? - MySQL FAQs - Introduction to SQL Basics Both CHAR and NCHAR are fixed length string data types. But they have the following differences: CHAR's full name is CHARACTER. NCHAR's full name is NATIONAL CHARACTER. By default, CHAR uses ASCII character se... 2007-05-11, 4815👍, 0💬

What Are the Differences between BINARY and VARBINARY
What Are the Differences between BINARY and VARBINARY? - MySQL FAQs - Introduction to SQL Basics Both BINARY and VARBINARY are both binary byte data types. But they have the following major differences: BINARY stores values in fixed lengths. Values are padded with 0x00. VARBINARY stores values in va... 2007-05-11, 4775👍, 0💬

All rights in the contents of this web site are reserved by the individual author. fyicenter.com does not guarantee the truthfulness, accuracy, or reliability of any contents.