Trouble with running a shell script

[Geeta Rajaraman]

Hello there -
I've been trying to create a simple "check" script, that tries to insert and delete a row into the database, just to check general database health.
It looks something like this:
------------------
DBNAME="$1"
USER="$2"
PASSWORD="$3"
TABLENAME="$4"
MYSQL_HOME=/var/lib/mysql/db_5.1.47

# Try to determine MYSQLHOME
if [ -z "$MYSQL_HOME" ]
then
MYSQL_HOME="$(egrep ':(Y|N)$' /var/lib/mysql/mysqltab | head -n 1 | cut -d: -f2)"
fi

if [ -z "$MYSQL_HOME" ]
then
echo "MYSQL_HOME not set, also cannot determine that from /var/lib/mysql/mysqltab." >&2
exit $STATE_UNKNOWN
fi

export MYSQL_HOME

MYSQL="$(which mysql)"

if [ ! -x "$MYSQL" ]
then
echo "Cannot find mysql in $MYSQL" >&2
exit $STATE_UNKNOWN
fi

AUTHENTICATION="-u$USER -h localhost -p$PASSWORD"

OUTPUT=$(mysql $AUTHENTICATION $DBNAME -e "INSERT INTO $TABLENAME(a) VALUES(3);DELETE FROM $TABLENAME")

echo $OUTPUT

---------------

But, OUTPUT is always empty. I wanted to see something like "1 row affected" which would let me process a conditional query that can check for database health issues.

Can someone please help me with this ? I'd like to know what I'm doing wrong.

Thanks much