mysql多个不同表不同结构合并查询,并集查询多个不同表结构数据，部分表结构相同，部分表结构不同的查询方式union All的实现
需求背景
商品表分为三个：基础商品表【aidong_goods】、一存多品商品表【aidong_goods_unit_sku】、一品多存商品表【aidong_goods_specs_sku】
基础商品表和其他两张表有关联id，并三张表部分字段不同，部分字段相同，需要根据条件过滤聚合查询出三张表的商品数据并合并！
实现方式
1.通过查询主商品后再查询其他关联商品
缺点是不方便分页查询，还需要循环，速度和性能都可能受到较大影响
2.关联查询
缺点是无法直接并集拿到数据
3.通过union all实现联合查询
union会过滤数据，所以采用union all
其他方式暂时未考虑采用，比如子查询、临时表、视图查询
具体实现
通过union all实现联合查询，并结合join实现复杂的条件查询。以及自定义字段的命名解决不同表结构问题，使用子查询包含后可以实现整体分页和条件查询
SELECT
t.*
FROM
(
SELECT
aidong_goods.goods_id,
aidong_goods.tenant_id,
aidong_goods.shop_id,
aidong_goods.goods_sn,
aidong_goods.goods_name,
aidong_goods.goods_img,
aidong_goods.brand_id,
aidong_goods.market_price,
aidong_goods.selling_price,
aidong_goods.selling_stock,
aidong_goods.limit_selling_stock,
aidong_goods.storage_room_stock,
aidong_goods.invented_sale_count,
aidong_goods.reality_sale_count,
aidong_goods.unit_id,
aidong_goods.goods_describe,
aidong_goods.is_shelves,
aidong_goods.sys_cat_id1,
aidong_goods.sys_cat_id2,
aidong_goods.sys_cat_id3,
aidong_goods.shop_cat_id1,
aidong_goods.shop_cat_id2,
aidong_goods.data_flag,
aidong_goods.create_time,
aidong_goods.mark_icon,
aidong_goods.is_standard_commodity,
aidong_goods.intelligence_remark,
aidong_goods.shop_goods_sort,
aidong_goods.goods_distribution,
aidong_goods.member_price,
aidong_goods.integral_reward,
aidong_goods.goods_type,
aidong_goods.stock_warning_num,
aidong_goods.integral_rate,
aidong_goods.buy_num_limit,
aidong_goods.min_buy_num,
aidong_goods.is_becyclebin,
aidong_goods.limit_daily_day,
aidong_goods.DELAYED,
aidong_goods.plu_code,
aidong_goods.vedio_url,
aidong_goods.py_initials,
aidong_goods.international_bar_code,
aidong_goods.recent_purchase_price,
aidong_goods.purchase_type,
aidong_goods.supplier_id_or_buyer_id,
aidong_goods.quality_guarantee_period,
aidong_goods.goods_alias,
aidong_goods.is_sale,
aidong_goods.weight,
aidong_goods.volume,
aidong_goods.to_be_weighed_type,
aidong_goods.individual_enterprise_main_show,
aidong_goods.individual_enterprise_limit_purchase_show,
aidong_goods.producer,
aidong_goods.processing_mode_status,
aidong_goods.is_free_shipping,
aidong_goods.delivery_freight_template_id,
aidong_goods.inventory_deduction_type,
aidong_goods.is_enable_batch,
aidong_goods.room_stock_avg_price,
aidong_goods.loss_rate,
0 AS sku_id,
0 AS unit_transform_num
FROM
aidong_goods
UNION ALL
SELECT
aidong_goods_unit_sku.goods_id,
aidong_goods_unit_sku.tenant_id,
aidong_goods_unit_sku.shop_id,
aidong_goods_unit_sku.goods_sn,
aidong_goods.goods_name,
aidong_goods.goods_img,
aidong_goods.brand_id,
aidong_goods_unit_sku.market_price,
aidong_goods_unit_sku.selling_price,
aidong_goods_unit_sku.selling_stock,
aidong_goods_unit_sku.limit_selling_stock,
aidong_goods.storage_room_stock,
aidong_goods.invented_sale_count,
aidong_goods.reality_sale_count,
aidong_goods_unit_sku.unit_id,
aidong_goods_unit_sku.goods_describe,
aidong_goods.is_shelves,
aidong_goods.sys_cat_id1,
aidong_goods.sys_cat_id2,
aidong_goods.sys_cat_id3,
aidong_goods.shop_cat_id1,
aidong_goods.shop_cat_id2,
aidong_goods_unit_sku.data_flag,
aidong_goods.create_time,
aidong_goods.mark_icon,
aidong_goods_unit_sku.is_standard_commodity,
aidong_goods.intelligence_remark,
aidong_goods.shop_goods_sort,
aidong_goods.goods_distribution,
aidong_goods_unit_sku.member_price,
aidong_goods.integral_reward,
aidong_goods.goods_type,
aidong_goods.stock_warning_num,
aidong_goods_unit_sku.integral_rate,
aidong_goods_unit_sku.buy_num_limit,
aidong_goods_unit_sku.min_buy_num,
aidong_goods.is_becyclebin,
aidong_goods_unit_sku.limit_daily_day,
aidong_goods.DELAYED,
aidong_goods_unit_sku.plu_code,
aidong_goods.vedio_url,
aidong_goods.py_initials,
aidong_goods_unit_sku.international_bar_code,
aidong_goods.recent_purchase_price,
aidong_goods.purchase_type,
aidong_goods.supplier_id_or_buyer_id,
aidong_goods.quality_guarantee_period,
aidong_goods.goods_alias,
aidong_goods_unit_sku.is_sale,
aidong_goods_unit_sku.weight,
aidong_goods_unit_sku.volume,
aidong_goods_unit_sku.to_be_weighed_type,
aidong_goods_unit_sku.individual_enterprise_main_show,
aidong_goods_unit_sku.individual_enterprise_limit_purchase_show,
aidong_goods.producer,
aidong_goods.processing_mode_status,
aidong_goods.is_free_shipping,
aidong_goods.delivery_freight_template_id,
aidong_goods.inventory_deduction_type,
aidong_goods.is_enable_batch,
aidong_goods.room_stock_avg_price,
aidong_goods.loss_rate,
aidong_goods_unit_sku.sku_id,
aidong_goods_unit_sku.unit_transform_num
FROM
aidong_goods
RIGHT JOIN aidong_goods_unit_sku ON aidong_goods.goods_id = aidong_goods_unit_sku.goods_id
UNION ALL
SELECT
aidong_goods_specs_sku.goods_id,
aidong_goods_specs_sku.tenant_id,
aidong_goods_specs_sku.shop_id,
aidong_goods_specs_sku.goods_sn,
aidong_goods.goods_name,
aidong_goods_specs_sku.goods_img,
aidong_goods.brand_id,
aidong_goods_specs_sku.market_price,
aidong_goods_specs_sku.selling_price,
aidong_goods_specs_sku.selling_stock,
aidong_goods_specs_sku.limit_selling_stock,
aidong_goods_specs_sku.storage_room_stock,
aidong_goods_specs_sku.invented_sale_count,
aidong_goods_specs_sku.reality_sale_count,
aidong_goods_specs_sku.unit_id,
aidong_goods_specs_sku.goods_describe,
aidong_goods.is_shelves,
aidong_goods.sys_cat_id1,
aidong_goods.sys_cat_id2,
aidong_goods.sys_cat_id3,
aidong_goods.shop_cat_id1,
aidong_goods.shop_cat_id2,
aidong_goods_specs_sku.data_flag,
aidong_goods.create_time,
aidong_goods.mark_icon,
aidong_goods_specs_sku.is_standard_commodity,
aidong_goods.intelligence_remark,
aidong_goods.shop_goods_sort,
aidong_goods.goods_distribution,
aidong_goods_specs_sku.member_price,
aidong_goods.integral_reward,
aidong_goods.goods_type,
aidong_goods_specs_sku.stock_warning_num,
aidong_goods_specs_sku.integral_rate,
aidong_goods_specs_sku.buy_num_limit,
aidong_goods_specs_sku.min_buy_num,
aidong_goods.is_becyclebin,
aidong_goods_specs_sku.limit_daily_day,
aidong_goods_specs_sku.delayed,
aidong_goods_specs_sku.plu_code,
aidong_goods.vedio_url,
aidong_goods.py_initials,
aidong_goods_specs_sku.international_bar_code,
aidong_goods_specs_sku.recent_purchase_price,
aidong_goods.purchase_type,
aidong_goods.supplier_id_or_buyer_id,
aidong_goods.quality_guarantee_period,
aidong_goods.goods_alias,
aidong_goods_specs_sku.is_sale,
aidong_goods_specs_sku.weight,
aidong_goods_specs_sku.volume,
aidong_goods_specs_sku.to_be_weighed_type,
aidong_goods_specs_sku.individual_enterprise_main_show,
aidong_goods_specs_sku.individual_enterprise_limit_purchase_show,
aidong_goods.producer,
aidong_goods.processing_mode_status,
aidong_goods.is_free_shipping,
aidong_goods.delivery_freight_template_id,
aidong_goods.inventory_deduction_type,
aidong_goods.is_enable_batch,
aidong_goods_specs_sku.room_stock_avg_price,
aidong_goods.loss_rate,
aidong_goods_specs_sku.sku_id,
0 AS unit_transform_num
FROM
aidong_goods
RIGHT JOIN aidong_goods_specs_sku ON aidong_goods.goods_id = aidong_goods_specs_sku.goods_id
) t
where goods_name="西瓜"
limit 1,10
注意事项
自定义字段时 比如数字的可以给 0 as xxx 字符串 '' as xxx
字段顺序不能出错 否则聚合出来的数据字段不正确
如果是强类型语言可以自己对比处理，例如自动生成自定义字段以及字段类型和别名。以上的sql就是在go环境下通过获取表模型自动生成的，不然手工定义大量字段还要做好一一对应实属不方便
运行结果
