Column Type Conversion

Question

Hi All,
I have an ERP which is being upgraded to a newer version along with the backend Oracle database from 8i to 10g. The old version has so many tables with CHAR type columns and the vendor is overcharging (yeah..its normal) us for the conversion. Is there a method which I can try to get the tables scanned one by one and then converted to VARCHAR2 and then the data inserted with ALLTRIM or a similar method. I am looking at a solution that can give me the least amount of downtime and faster results.
Thank you,
JeeKay
Message was edited by:
user577864
Message was edited by:
user577864

Answer 1

Hi,
You may want to try this:
SQL> set pages 0
SQL> spool c:\windows\temp\modichar.sql
Started spooling to c:\windows\temp\modichar.sql
SQL> select 'alter table "' || t.OWNER || '"."' || t.TABLE_NAME || '" modify "' || t.COLUMN_NAME || '" VARCHAR2(' || t.DATA_LENGTH || ');'
  2  from dba_tab_columns t inner join dba_tables dt on t.owner = dt.owner and t.TABLE_NAME = dt.table_name
  3  where t.DATA_TYPE = 'CHAR' and t.owner IN ('TEST');
alter table "TEST"."ZTEST" modify "STRI" VARCHAR2(10);
SQL> spool off
Stopped spooling to c:\windows\temp\modichar.sql
SQL> @c:\windows\temp\modichar.sql
SQL> alter table "TEST"."ZTEST" modify "STRI" VARCHAR2(10);
Table alteredSimilar idea can be used to eliminate trailing spaces.