How to resolve ORA-01448 Error Message in Oracle database

Learn the cause and how to resolve the ORA-01448 error message in Oracle.


When you stumble upon an ORA-01448 error, the following error message will appear:

ORA-01448: index need to be dropped before altering to preferred type


You tried to execute a ALTER TABLE MODIFY attempting to change the information kind of an listed column to a LONG datatype. Columns with the LONG datatype can no longer be indexed.


The option(s) to resolve this Oracle error are:

Option #1

Drop all indexes that reference the column that you want to alternate to a LONG datatype.

Option #2

Select a different column to index.

For example, if you had a table known as suppliers defined as follows:

CREATE TABLE suppliers
( supplier_name varchar2(50),
  city varchar2(35),
  state varchar2(2),
  zip varchar2(10),
  CONSTRAINT suppliers_pk PRIMARY KEY (supplier_name) 

Then executed the following ALTER TABLE statement

ALTER TABLE suppliers
 MODIFY supplier_name LONG;

You would receive the following error message:

You may want to right the error with the aid of disposing of the most important key from the suppliers table:

ALTER TABLE suppliers
 DROP CONSTRAINT suppliers_pk;

However, once you have modified to your column to a LONG datatype, you can no longer include this column in any index.