dynamic sql problem

HI,

I am running a stored procdures which contains following dynamic sql ..i am getting error:
ORA-00936 missing expression......... for the bold statement while rest of statements r properly executing......
what might be the reason......
and temp_ are variables declared...... and name1,name2,name3 are dynamically generated table names..........

str := 'alter table'||' '||name2||' '||'disable constraint'||'
'||temp1_cons;

execute immediate str;
str := 'alter table'||' '||name3||' '||'disable constraint'||' '||temp_cons; execute immediate str;
str :='update '||' '||name2||' '||' set id_sess=id_sess + '||'
'||temp_id_sess_2;

execute immediate str;
str :='update '||' '||name3||' '||' set id_sess = id_sess +'||'
'||temp_id_sess_3;

execute immediate str;
str :='create table'||' '||enum||' '||'as select * from'||' '||name1||'
'||'union

select * from'||' '||name2||' '||'union select * from'||' '||name3; execute immediate str;

Thanks
Harvinder

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Author: Harvinder Singh
  INET: Harvinder.Singh_at_MetraTech.com

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