I'm getting an else unmatched error on the script below..

For info : SYDB is the database name entered as a param on the command line.

#Check the DB name
HBDB=`sql $SYDB <<_END_ | grep '^|' | grep -v dbase | sed 's/|//g' | sed 's/ //g'
set autocommit on;
\p\g
set lockmode session where readlock = nolock;
\p\g
select squeeze(trim(dbase)) as dbase
from syapplic
where applic_id = 'hb';
\p\g
_END_`

if [ -z "$HBDB" ]
then
echo "The HB Database name given is not a valid database!"
exit 1
else
echo "The Hb database name is $HBDB "
echo " "
fi

# Declare variables for output
MAINFOLDER=/*server location*/sig10
FILEDATE=`date +%Y%m%d`
FILETIME=`date +%H:%M:%S`
OUTPUTFILE="$MAINFOLDER/Sig_Birthdays_10_$FILEDATE.csv"

#check that the comparison tale exists withing the HBDB
TBL_CHECK=`sql $HBDB <<_END_ | grep '^|' | grep -v table_name | sed 's/|//g' | sed 's/ //g'
set autocommit on;
\p\g
set lockmode session where readlock = nolock;
\p\g
select table_name
from iitables
where table_name = 'bh_sig_10';
\p\g
_END_`

echo $TBL_CHECK

if [ "$TBL_CHECK" = "bh_sig_10" ]
then
echo "Comparison table exists"
else
echo "Comparison table does not exist - Script will create table"
sql $HBDB <<_END_ > $MAINFOLDER/Create_comparison_table.txt
set autocommit on;
\p\g
set lockmode session where readlock = nolock;
\p\g
create table bh_sig_10 (
claim_id i4,
title varchar 4,
forename varchar 32,
surname varchar 32,
birth_date date
)
with nojournaling,
noduplicates;
\p\g
_END_
fi
...

I get the else unmatched on that else in bold....any clues?