Example table prefix in wp multisite/ not

smpleprfx.php

<?php
if ( is_multisite() ) :
	global $wpdb, $table_prefix;
	$table_name = $table_prefix . 'postmeta'; // output wp_#_postmeta (multisite) # = id multisite (automatic)
	$select_data = $wpdb->get_results( "SELECT meta_value FROM $table_name WHERE meta_value = '$warrior_url_topic'" );
	$check_url_exists = $wpdb->num_rows;

	foreach ( $select_data as $obj ) {
		$wp_data = $obj->meta_value;
	}
else :
	global $wpdb;
	$table_name = $wpdb->base_prefix . 'postmeta'; // output wp_postmeta (not multisite)
	$select_data = $wpdb->get_results( "SELECT meta_value FROM $table_name WHERE meta_value = '$warrior_url_topic'" );
	$check_url_exists = $wpdb->num_rows;

	foreach ( $select_data as $obj ) {
		$wp_data = $obj->meta_value;
	}
endif;
?>