How I could check connectivity in shell using an oneliner command without using netcat?

In a docker image I want to avoid installing netcat in order to ping for db connectivity at my entrypoint script:

/bin/sh

MOODLE_DB_HOST="xxxx"
MOODLE_DB_PORT=80

function pingdb {
    OK=0
    for count in {1..100}; do
      echo "Pinging database attempt ${count} into ${MOODLE_DB_HOST}:${MOODLE_DB_PORT}" 
      if  $(nc -z ${MOODLE_DB_HOST} ${MOODLE_DB_PORT}) ; then
        echo "Can connect into database"
        OK=1
        break
      fi
      sleep 5
    done

    echo "Is ok? "$OK

    if [ $OK -eq 1 ]; then
      echo "Database type: "${MOODLE_DB_TYPE}
      echo "DB Type: "${MOODLE_DB_TYPE}
    else
      echo >&2 "Can't connect into database"
      exit 1
    fi
}

But instead, I want to use a nc replacement for entrypoint script running upon docker images utilising php. Is there an alternative? The reason why I want to do this is because I have 2 Dockerfiles, one debian-based and one alpine based: debian-based php image:

ARG PHP_VERSION="7.4"
FROM  php:${PHP_VERSION}-fpm as base

RUN --mount=type=bind,from=mlocati/php-extension-installer:latest,source=/usr/bin/install-php-extensions,target=/usr/local/bin/install-php-extensions \
	/usr/local/bin/install-php-extensions xmlrpc mbstring zip xml intl soap gd opcache &&\
	echo "PHP_EXTENTION_DIR="$(php -i | grep extension_dir  | cut -d " " -f 5) >> /etc/environment &&\
	cat /etc/environment &&\
	apt-get update &&\
	apt-get install -y netcat &&\
 	apt-get autopurge -y &&\
 	apt-get autoremove -y &&\
 	apt-get autoclean &&\
 	rm -rf /var/lib/apt/lists/* /tmp/* /var/tmp/* cache/* /var/lib/log/* &&\
	echo "max_input_vars=5000" > ${PHP_INI_DIR}/conf.d/moodle.ini

COPY ./scripts/entrypoint.sh /usr/local/bin/entrypoint.sh

RUN chown root:root /usr/local/bin/entrypoint.sh &&\
	chmod +x /usr/local/bin/entrypoint.sh

ENTRYPOINT ["/bin/sh","/usr/local/bin/entrypoint.sh"]
CMD ["php-fpm"]

And alpine-based:

ARG PHP_VERSION="7.4"
FROM  php:${PHP_VERSION}-fpm-alpine as base

RUN --mount=type=bind,from=mlocati/php-extension-installer:latest,source=/usr/bin/install-php-extensions,target=/usr/local/bin/install-php-extensions \
	/usr/local/bin/install-php-extensions xmlrpc mbstring zip xml intl soap gd opcache &&\
	apk update &&\
	apk add netcat-openbsd &&\
	 rm -rf /var/cache/apk/* /var/tmp/* cache/* /var/lib/log/* &&\
	echo "max_input_vars=5000" > ${PHP_INI_DIR}/conf.d/moodle.ini

COPY ./scripts/entrypoint.sh /usr/local/bin/entrypoint.sh

RUN chown root:root /usr/local/bin/entrypoint.sh &&\
	chmod +x /usr/local/bin/entrypoint.sh

ENTRYPOINT ["/bin/sh","/usr/local/bin/entrypoint.sh"]
CMD ["php-fpm"]

And sometimes depending the argument of PHP_VERSION may or may not the package for installing netcat do exist (or exist with different names). Also apk add and apt-get increases the build times significally as well. So is there an alternative approach?