ORA-06502: PL/SQL: numeric or value error: character string buffer too small

Question

I tried the following code different ways, like by taking out the while or the if, but when I put both together (if and while), I always get the error at the end...

Answer 1

CHAR is a fixed-length data type that uses as much space as possible. So a:= a||'one '; will require more space than is available. Your problem can be reduced to the following example:

declare
  v_foo char(50);
begin
  v_foo := 'A';
  dbms_output.put_line('length of v_foo(A) = ' || length(v_foo));
  -- next line will raise:
  -- ORA-06502: PL/SQL: numeric or value error: character string buffer too small
  v_foo := v_foo || 'B';
  dbms_output.put_line('length of v_foo(AB) = ' || length(v_foo));  
end;
/

Never use char. For rationale check the following question (read also the links):

• Oracle datatype: Should I use VARCHAR2 or CHAR

Answer 2

This may also happen if you have a faulty or accidental equation in your csv file. i.e - One of the cells in your csv file starts with an equals sign (=) (An excel equation) which will, in turn throw an error. If you fix, or remove this equation by getting rid of the equals sign, it should solve the ORA-06502 error.

Answer 3

PL/SQL: numeric or value error: character string buffer too small

is due to the fact that you declare a string to be of a fixed length (say 20), and at some point in your code you assign it a value whose length exceeds what you declared.

for example:

myString VARCHAR2(20);
myString :='abcdefghijklmnopqrstuvwxyz'; --length 26

will fire such an error