Select problem from view.

Question

Hi everyone,
<br><br>
I have constructed the following view,
<br><br>
SELECT b.eml_id
     , a.email "FROM"    
     , to_address.name
     , to_address.role
     , to_address.email "TO"
     , to_address.subject
     , to_address.header
     , to_address.footer   
  FROM mySchema.sct_parties a    
     , mySchema.sct_email_notify b
     , mySchema.sct_assign_email_notify c
     , (SELECT e.eml_id
             , c.name "ROLE"
             , initcap(a.first || ' ' || a.last) "NAME"            
             , a.email
             , e.subject
             , e.header
             , e.footer
          FROM mySchema.sct_parties a
             , mySchema.sct_assign_roles b
             , mySchema.sct_roles c
             , mySchema.sct_assign_email_notify d
             , mySchema.sct_email_notify e
         WHERE a.par_id = b.par_id
           AND b.rle_id = c.rle_id
           AND c.rle_id = d.rle_id
           AND d.eml_id = e.eml_id
           AND d.rle_id = 6
           AND e.status = 'CURRENT') to_address
WHERE a.par_id = b.par_id
   AND to_address.eml_id = b.eml_id
   AND b.eml_id = 1
   AND b.status = 'CURRENT'When I do a
<br><br>
select * from viewName
<br><br>
no worries I get the record returned as expected, but when I
<br><br>
select a.to from viewName a I get the following error
<br><br>
Error starting at line 1 in command:
SELECT a.to
  FROM mySchema.viewName a
Error at Command Line:1 Column:9
Error report:
SQL Error: ORA-01747: invalid user.table.column, table.column, or column specification
01747. 00000 -  "invalid user.table.column, table.column, or column specification"
*Cause:   
*Action:<br><br>
Could someone tell me what the problem is.
<br><br>
Ben

Answer 1

Double quotes may be confusing if the case is not consistent. Also, Oracle will use upper case in the data dictionary, by default, unless you use double quotes.
SQL> create table t("col1" number, col2 number)
Table created.
SQL> insert into t(col1) values (1)
ORA-00904: "COL1": invalid identifier
SQL> insert into t(col2) values (2)
1 row created.
SQL> select col1 from t
ORA-00904: "COL1": invalid identifier
SQL> select col2 from t
      COL2
         2
1 row selected.
SQL> select column_name from user_tab_columns
where table_name = 'T'
and column_name like 'COL%'
COLUMN_NAME                  
COL2                         
1 row selected.