7 Replies Latest reply on Mar 18, 2014 10:44 AM by Mr.D.

    Alter table modify very slow

    Mr.D.

      Hi,

      i'm trying to modify a semantic  of a column in a table.

       

      ALTER TABLE MYTAB MODIFY (MYCOL VARCHAR2(100 CHAR));

       

      This command produce db file sequential read wait event and it's very very slow.

      On some other table it performs a scattered read.

       

      I'm in 11.2.0.3 EE on Linux 64bit

       

      How can i avoid db file sequential read wait event?