Oracle's SUBSTR function

SUBSTR (string, intercept start position, intercept length)//return intercepted word

substr (' Hello World ', 0, 1)//return result is ' H ' * start with a string of length 1 from the first character

substr (' Hello World ', 1, 1)//Returns the result for ' H ' *0 and 1 is the first character that represents the start position of the Intercept

substr (' Hello world ', 2,4)//return result as ' Ello '

substr (' Hello world ', -3,3)//Returns the result as ' rld ' * negative (-i) to indicate the start of the intercept is the left number I character of the right end of the string

Test:

Select substr (' Hello world ', -3,3) value from dual;

Attached: Simple usage of substring (INDEX1,INDEX2) in Java

Function: begins to intercept a string of length index2-index1 from a character string index (subscript) of index1.

String str= "Hello World";

System.out.println (str.substring (0,5));

Print Result: Hello

Oracle's SUBSTR function