특정 컬럼 배열로 가져오기[ array_to_string ]

	<select id="getCustIdArray" resultType="string">
		/* custDAO.getCustIdArray */ 
		SELECT
		 array_to_string( 
			 ARRAY(
				select cust_id from tn_cust
			  )
		  , ', ') AS all_cust_id
	</select>