program:

open ($input, "<", "/root/tables");
while (<$input>) {
table\s+([^{]+)\s+\{;
print $1;
}

close ($input);

sample from /root/tables/

create table dg_set(
        dg_seq integer not null,
        wc_seq integer not null,
        dg_name varchar(20) not null,
        comment varchar(50) not null
)


program output: nothing