Differences Between CHAR and VARCHAR2 Data Types
- Predefined Subtypes
- How Blank-Padding Works
- Value Comparisons
:
CHAR and VARCHAR2 Blank-Padding Difference
In this example, both the CHAR variable and the VARCHAR2 variable have the maximum size of 10 characters. Each variable receives a five-character value with one trailing blank. The value assigned to the CHAR variable is blank-padded to 10 characters
DECLARE
first_name CHAR(10);
last_name VARCHAR2(10);
BEGIN
first_name := 'Rama ';
last_name := 'Nyrk ';
DBMS_OUTPUT.PUT_LINE('*' || first_name || '*');
DBMS_OUTPUT.PUT_LINE('*' || last_name || '*');
END;
/
Result:
*Rama *
*Nyrk *
Value Comparisons
The SQL rules for comparing character values apply to PL/SQL character variables.
Whenever one or both values in the comparison have the data type VARCHAR2, nonpadded comparison semantics apply; otherwise, blank-padded semantics apply.
