Menu
The concatenation operator manipulates character strings and CLOB data.
The concatenation operators combine two strings to form one string by appending the second string to the right-hand end of the first string. The concatenation might occur with or without an intervening blank.
The || Operator in PLSQL is used to concatenate 2 or more strings together. The result of concatenating two character strings is another character string.
In formal language theory and computer programming, string concatenation is the operation of joining character strings end-to-end. For example, the concatenation of "snow" and "ball" is "snowball".
It is ||, for example:
select 'Mr ' || ename from emp;
The only "interesting" feature I can think of is that 'x' || null returns 'x', not null as you might perhaps expect.
There's also concat, but it doesn't get used much
select concat('a','b') from dual;
I would suggest concat when dealing with 2 strings, and || when those strings are more than 2:
select concat(a,b)
from dual
or
select 'a'||'b'||'c'||'d'
from dual
DECLARE
a VARCHAR2(30);
b VARCHAR2(30);
c VARCHAR2(30);
BEGIN
a := ' Abc ';
b := ' def ';
c := a || b;
DBMS_OUTPUT.PUT_LINE(c);
END;
output:: Abc def
Using CONCAT(CONCAT(,),) worked for me when concatenating more than two strings.
My problem required working with date strings (only) and creating YYYYMMDD from YYYY-MM-DD as follows (i.e. without converting to date format):
CONCAT(CONCAT(SUBSTR(DATECOL,1,4),SUBSTR(DATECOL,6,2)),SUBSTR(DATECOL,9,2)) AS YYYYMMDD
If you love us? You can donate to us via Paypal or buy me a coffee so we can maintain and grow! Thank you!
Donate Us With