A couple of things...

First, remove the ";" after the "fi"
also, if $all_recs is from the command line,
I assume you are assigning it...

export all_recs=$1


Second, try changing:
sqlplus -s $connect_string > /dev/null << EOF

to:
sqlplus -s $connect_string << EOF > /dev/null

...the second part should not have anything
to do with the "unmatched then" but it may cause
you execution problems. Additionally, the "if"
command is a shell built-in and would be
documented in the KSH(1) man page (assuming you
are using ksh (just man the shell you use).