SQL Functions - LENGTH, ASCII, SUBSTR

In this article we will discuss few SQL functions useful while working daily. SQL functions are kind of predefined packages/procedure, can be used in different aspects, lets discuss one by one

LENGTH

Syntax - LENGTH(String)

This function returns the total number of characters present in the string

Example

SQL>  SELECT LENGTH('Interest') from dual;

 

LENGTH('INTEREST')

------------------

                 8

 

ASCII

Syntax – ASCII(char)

This function gives ASCII value of given character

Example

SQL>  SELECT ASCII('B') from dual;

 

ASCII('B')

----------

        66

 

SQL>  SELECT ASCII('I') from dual;

 

ASCII('I')

----------

        73

 

SUBSTR

Syntax - SUBSTR (string, position, sub-string_length)

This substring function return a portion of string, starting at character position, sub-string_length characters long.

SUBSTR calculates length using characters as defined by the input character set

SQL> select SUBSTR('entertainment',4,10) from dual;

 

SUBSTR('EN

----------

ertainment

 

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