SQL CONCAT scalar function in DB2 for i SQL

SQL CONCAT scalar function in DB2 for i SQL

CONCAT

The CONCAT function combines two arguments to form a string expression. Both the arguments must be compatible. The result is NULL if any argument is NULL value.

Syntax

CONCAT(expression1,expression2)

Example#1:

SELECT CONCAT('A', 'B') FROM SYSIBM.SYSDUMMY1

Here, both the strings gets combined and not null result will be returned.

CONCAT
  AB  

Example#2:

SELECT CONCAT('NULL', 'A') FROM SYSIBM.SYSDUMMY1

Or

SELECT CONCAT('A', NULL) FROM SYSIBM.SYSDUMMY1

Or

SELECT CONCAT(NULL, NULL) FROM SYSIBM.SYSDUMMY1

Here, return result will be NULL if at least one argument is NULL value

CONCAT
  -   

Example#3:

SELECT CONCAT(1,2) OM SYSIBM.SYSDUMMY1

Here, Either any of the argument can be numeric datatype and they will be combined and casted implicitly to a VARCHAR data type

CONCAT ( 1 , 2 )
12              

Or

SELECT CONCAT(1,'A') OM SYSIBM.SYSDUMMY1

CONCAT ( 1 , 'A' )
1A