SQLplus decode to execute scripts

Question

I am writing a script to be run in sqlplus 11. I have a user defined variable called compression. If this is true then I want to run the script CreateTablesCompression, otherwise run. I have the following:

decode(compression,'true',@@CreateTablesCompression,@@CreateTables);

However,when I run this I am thrown the error: unknown command beginning "decode...

Am I missing something here, I can't see why SQLPlus wouldn't recognise decode?

Answer 1

Decode is not a SQL*PLUS command, you cannot use it directly in sql*plus only inside a pl/sql block or a query. So here is an example of how a conditional branching can be done: We declare a variable flag which going to regulate which one of two available scripts to run.

SQL> variable flag varchar2(7);
SQL> exec :flag := 'true';

PL/SQL procedure successfully completed.

SQL> column our_script new_value script noprint;
SQL> select decode(:flag, 'true', 
  2                'c:\sqlplus\script1.sql', 
  3                'c:\sqlplus\script2.sql'
  4                ) our_script
  5  from dual;




SQL> @&script;

SCRIPT                                                                          
--------                                                                        
script_1                                                                        

Answer 2

SQL> host cat foo.sql
set scan on
define compression=&1
col scr new_value script
set term off
select decode('&compression', 'true', 'CreateTablesCompression', 'CreateTables') scr from dual;
set term on
@@&script

SQL> @foo true
run CreateTablesCompression.sql
SQL> @foo false
run CreateTables.sql