Delete question-how to delete a php product category?

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Your location: item category column Category ID category tree Category name parent category ID parent category path item category management 6 appliances 0 0, modify | copy | delete 15 black/white TV sets 6, modify | copy | delete 27 washing machine 6, modify | copy | delete 28 LCD TV 6, modify | copy | delete 3 Women's 0, modify | copy | delete 12 casual pants 3, modify | copy | delete 7 mobile phones 0 0, modify | copy | delete 8 iphone 7, modify | copy | delete 10 iphone6s 8, 8. modify | copy | delete 9 Huawei 7, modify | copy | delete 11 Huawei mate9 9, modify | copy | delete 19 vivo 7, modify | copy | delete 26 vivoX7 19 0, 7, 19, modify | copy | delete // How to make items in the table above Category deletion? Delete parent category = parent + child $ id =_ _ GET ['id']; $ SQL = "select path from type WHERE path like '% $ id %'"; $ rs = mysql_query ($ SQL); $ arr = mysql_fetch_assoc ($ rs ); if ($ arr) {$ path = "and path like '% $ id %'";} else {$ path = '';} $ where = "where id = {$ id} {$ path}"; $ sql2 = "delete from type $ where"; // echo $ sql2; die (); $ rs = mysql_query ($ sql2); if (mysql_affected_rows ()> 0) {echo 'deletion successfully';} else {echo 'deletion failed';} break; // why can't I delete products with subcategories in my code? Can the parent class be executed only after the sub-category is deleted? // is the sequence problem of where and? For example, if you want to delete a women's dress, you need to delete the casual trousers first. but what should I do if I want to delete them directly ??

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Your location: item category column Category ID category tree Category name parent category ID parent category path item category management 6 appliances 0 0, modify | copy | delete 15 black/white TV sets 6, modify | copy | delete 27 washing machine 6, modify | copy | delete 28 LCD TV 6, modify | copy | delete 3 Women's 0, modify | copy | delete 12 casual pants 3, modify | copy | delete 7 mobile phones 0 0, modify | copy | delete 8 iphone 7, modify | copy | delete 10 iphone6s 8, 8. modify | copy | delete 9 Huawei 7, modify | copy | delete 11 Huawei mate9 9, modify | copy | delete 19 vivo 7, modify | copy | delete 26 vivoX7 19 0, 7, 19, modify | copy | delete // How to make items in the table above Category deletion? Delete parent category = parent + child $ id =_ _ GET ['id']; $ SQL = "select path from type WHERE path like '% $ id %'"; $ rs = mysql_query ($ SQL); $ arr = mysql_fetch_assoc ($ rs ); if ($ arr) {$ path = "and path like '% $ id %'";} else {$ path = '';} $ where = "where id = {$ id} {$ path}"; $ sql2 = "delete from type $ where"; // echo $ sql2; die (); $ rs = mysql_query ($ sql2); if (mysql_affected_rows ()> 0) {echo 'deletion successfully';} else {echo 'deletion failed';} break; // why can't I delete products with subcategories in my code? Can the parent class be executed only after the sub-category is deleted? // is the sequence problem of where and? For example, if you want to delete a women's dress, you need to delete the casual trousers first. but what should I do if I want to delete them directly ??

Delete from table where id = 7 or path like '%, 7, %'

Based on my experience, I have the following suggestions:
1. when you delete a product category, you must check the database to verify that the category contains a subcategory. If yes, you cannot delete the category.
2. before deleting a category, you must delete all the sub-categories under the category.
3. if you do not follow these steps, junk data will be generated.