invalid number of arguments while concatenating SQL-CodePudding

SELECT 
    HIRE_DATE, FIRST_NAME, LAST_NAME, 
    CONCAT(FIRST_NAME, ' ', LAST_NAME) AS "First and Last name" 
FROM HR.EMPLOYEES

I'm trying to get one column by concatenating two other, but i get an error

ORA-00909: invalid number of arguments

CodePudding user response：

In oracle concat() takes only two arguments. You can't use three instead. Here goes your solution.

SELECT 
    HIRE_DATE, FIRST_NAME, LAST_NAME, 
    CONCAT(CONCAT(FIRST_NAME, ' '), LAST_NAME) AS "First and Last name" 
FROM HR.EMPLOYEES

Or you can use || to concat more than two strings:

SELECT 
    HIRE_DATE, FIRST_NAME, LAST_NAME, 
    (FIRST_NAME || ' '|| LAST_NAME) AS "First and Last name" 
FROM HR.EMPLOYEES

CodePudding user response：

You can use Pipe Symbol '|' to concatenation of strings in oracle ..It can have multiple inputs/ columns .

Syntax : Col1 || col2|| ' '|| Col3|| ' Any String'||Col4

Select hire_date, First_name, Last_name, First_name || ' ' || Last_Name as "First and Last name"

From HR.Employees

You can also use concat() function but it will takes only two input ... You need to use multiple times if you have more than 2 inputs.