declare column_exists exception;
 pragma exception_init (column_exists , -01430);
 begin execute immediate 'ALTER TABLE BPE ADD (dhEmb VARCHAR2(25))';
exception when column_exists then null;
 end;
/
declare column_exists exception;
 pragma exception_init (column_exists , -01430);
 begin execute immediate 'ALTER TABLE BPE ADD (CST00 VARCHAR2(2))';
exception when column_exists then null;
 end;
/
declare column_exists exception;
 pragma exception_init (column_exists , -01430);
 begin execute immediate 'ALTER TABLE BPE ADD (CST20 VARCHAR2(2))';
exception when column_exists then null;
 end;
/
declare column_exists exception;
 pragma exception_init (column_exists , -01430);
 begin execute immediate 'ALTER TABLE BPE ADD (CST45 VARCHAR2(2))';
exception when column_exists then null;
 end;
/
declare column_exists exception;
 pragma exception_init (column_exists , -01430);
 begin execute immediate 'ALTER TABLE BPE ADD (CST90 VARCHAR2(2))';
exception when column_exists then null;
 end;