方法介绍
concat_ws(分隔符，需要拼接在一起的字段）
实例
SELECT
day_catering.S_ID,
day_catering.S_DAY_WEEKS_CAPTION,
concat_ws(
' , ',
BREAKFAST.RECIPE01_CAPTION,
BREAKFAST.RECIPE02_CAPTION,
BREAKFAST.RECIPE03_CAPTION,
BREAKFAST.RECIPE04_CAPTION,
BREAKFAST.RECIPE05_CAPTION
) AS BREAKFAST_RECIPE