MySQL operation

having and where The difference between

having（ Field ） Used to query the fields found ;
where ( Field ） Used to query fields that are purely in the database .

• having and where Can be used
  select goods_price,goods_name,goods_number from sw_goods where goods_price >100;
select goods_price,goods_name,goods_number from sw_goods having goods_price >100;

• Only use where Out of commission having The situation of
  SELECT goods_name,goods_number from sw_goods where goods_price>100;
SELECT goods_name,goods_number from sw_goods where goods_price>100;

• Only use having Out of commission where The situation of
  SELECT goods_category_id,avg(goods_price) as avg FROM sw_goods GROUP BY goods_category_id having avg>100;