Drop if exists in netezza

问题

I need a command to delete a table if that exists in NETEZZA, Something like that:

drop table if exists xxx;

I have searched and tried many but it didn't work. Can you help me here?

回答1:

In netezza you can use this syntax:

drop table table_name if exists;

回答2:

There is nothing built-in, but you can create a stored proc which uses the catalog views to check if the table exists before attempting to drop it:

create or replace procedure maybe_drop(varchar(128))
    returns boolean
    language nzplsql
as
begin_proc
declare
    oname alias for $1;
    o record;
begin
    select otype into o
    from (
        select 'TABLE' otype from _v_table where tablename = upper(oname)
        union all
        select 'VIEW' otype from _v_view where viewname = upper(oname)
    ) x;

    if found then
        execute immediate 'DROP '||o.otype||' '||oname;
    end if;
end;
end_proc;

来源：https://stackoverflow.com/questions/26624118/drop-if-exists-in-netezza