我想进行查询，从几个表中检索多个列

Question

I want something in PHP-mysql

I want to make one query, retrieve several or all columns from several tables

Example

query 1: "SELECT * FROM table1"
query 2: "SELECT * FROM table2"
query 2: "SELECT id,name FROM table3"
query 2: "SELECT num,num2 FROM table4"

And so on If you want to add more .

I want to combine all these queries in a single query .

Note: All queries doesn't associated with some, and also I do not want a problem occurs if the table is empty .

any helper here to help me

Answer 1

You need is some way to join the data together for example a column that exists in both tables that is common to each table

eg Accomodation database of sudents

Accomodation_table Accomodation_ID | Accomodation_Name

Student Table Student_ID | Student_Name | Accomodation_ID

Accomodation_ID is the common field

the query would look like this

Select a.Accomodation_Name, b.student_name
from Accomodation_table a, Student_Table b
where a.Accomodation_ID = b.Accomodation_ID