Question

I am looking for a fast sql sentence for determine when a field exist or not in a table .

actually i am using this sentence

Select 1 
   from dual
   where exists (select 1 
                   from all_tab_columns 
                  where table_name = 'MYTABLE' 
                    and column_name = 'MYCOLUMN')

I think there must be a fastest way to determine whether or not a column exist in ORACLE.

UPDATE

I’m optimizing a larger software system that makes multiple calls to this Query, I can not modify the source code ;( , only i can modify the query which is stored in an external file.

the Table all_tab_columns has over a million of records.

Answer 1

the primary key of all_tab_columns is owner, table_name, column_name so looking for a particular owner will be faster (or use user_tab_columns).