What is oracle Functions ?

Functions

These are oracle predefined functions ,which are used in sql statements.

Functions are two types:
 - Single Row Functions
 - Group Functions

Single Row Functions :

Single Row Functions different type some type are described below:

1. String Functions
2. Date Functions
3. Numeric Functions
4. Conversion Functions
5. Miscellaneous Functions
 
1. String Functions :

a. INITCAP : This is use to Capitalized first latter of a string.
Ex. Sql > select initcap('hello world') from dual;
output>
                 

b. UPPER : This is use to convert  a string into upper case.
Ex. Sql > select upper('hello world') from dual;
output>
           
c. LOWER : This is use to convert  a string into lower case.
Ex. Sql > select lower('HELLO world') from dual;
output>
            
d. LENGTH : This function is use to find length of a string.
Ex. Sql >select length('HELLO world') from dual;
output>
           

e. RPAD: This function is use to pads the right-side of a string  with a specific character or a set of characters (Default padding character is blank space)
Ex. Sql> select rpad('hello',9,'$'), rpad('hello',9,'$#') from dual;
output>
          


f. LPAD :This function is use to lads the left-side of a string  with a specific character or a set of characters  (Default padding character is blank space)
Ex. Sql> select lpad('hello',9,'$'), lpad('hello',9,'$#') from dual;
output>
          

g. LTRIM :This function is use to remove string's character from left side of the srting.
Ex. Sql> select ltrim('12heloo123','12345'), ltrim('heloo123','12345') from dual;
output>
          


h. RTRIM :This function is use to remove string's character from right side of the srting.
Ex. Sql> select rtrim('12heloo123','12345'),rtrim('heloo123','12345') from dual;
output>
         
       

i. TRIM : This function is use to remove unwanted character from both side of the string.
    LEADING,TRAILING and BOTH are three parameter use in TRIM function.
    BOTH is default parameter.
Ex. Sql>  select trim(leading'1'from'12reo123'), trim(trailing'3'from'33reo123'), trim(both'3'from'33reo123'), trim('3'from'33reoo123')  from dual;
output>
           


NOTE: TRIM set have only one character can't use more than one character.


Please share your in case of any further clarification on above post.