![](/img/trans.png)
[英]Mysql Query for fetching records using single Query from three tables
[英]Select three records in a single query of a cross table that contains records of two tables - MYSQL
我有一个称为"product"
的主表,该主表与三个表链接:
"product_type",
"feature",
"type_feature"
还有一个称为"product_feature"
的交叉表,其中包含同一产品的多个功能。
示例一记录:
我有类似的东西:
产品类别
id_product_type name
1 Phone
特征
id_feature name
1 Memory
2 Color
3 Memory Ram
FEATURE_TYPE
id_feature_type id_feature value
1 1 16GB
2 1 32GB
3 2 Blue
4 2 Black
5 3 2GB
6 3 3GB
产品
id_product id_product_type price quantity model
1 1 100$ 5 Moto-G7
交叉表“ product_feature”(链接到“ product”,“ feature”和“ feature_type”):
id_feature id_product id_feature_type
1 1 1
2 1 3
3 1 6
我想查询显示此:
id_product type_name price quantity model feature_name value
1 Phone 100$ 5 Moto-G7 Memory 16GB
feature_name2 value2 feature_name3 value3
Color Blue Memory Ram 3GB
我试过了,但是只有我只有一个feature_name和value,我需要三个:
SELECT p.id_product, pt.name, model, price, quantity, f.name AS feature, ft.value
FROM product p
LEFT JOIN product_type pt ON pt.id_product_type = p.id_product_type
LEFT JOIN product_feature pf ON pf.id_product = p.id_product
LEFT JOIN feature f ON f.id_feature = pf.id_feature
LEFT JOIN feature_type ft ON ft.id_feature_type = pf.id_feature_type
GROUP BY p.id_product;
试试这个查询,它将为您提供结果:
SELECT product.*, product_type.name as TypeName, (SELECT CONCAT( GROUP_CONCAT(feature_type.value), "|", GROUP_CONCAT(feature.name) ) FROM `product_feature` INNER JOIN feature_type on product_feature.id_feature_type = feature_type.id_feature_type INNER JOIN feature on feature_type.id_feature = feature.id_feature WHERE product_feature.id_product=1 GROUP BY product_feature.id_product) as options FROM `product` LEFT JOIN product_type on product.id_product_type = product_type.id_product_type
您将获得产品的选项,并且必须通过“ |”将这些选项炸开()。 并且您可以通过使用$ count = count(explode(“ |”,$ options))来计数您拥有多少个选项
通过这种方式,您可以获得所有选择。
声明:本站的技术帖子网页,遵循CC BY-SA 4.0协议,如果您需要转载,请注明本站网址或者原文地址。任何问题请咨询:yoyou2525@163.com.