PHP / MySQL-选择表1中的列等于表2中的列的所有行

Question

I am searching for a way that i can select all the rows from MySQL table where column from table1 is equal to column from table 2.

Here is what i want to achieve describing it by code. I tried this but nothing happens.

SELECT * FROM `table1` WHERE `table1.id`= `table2.id` ORDER by `table1.name` ASC; 

Can you give me a correct way to make this thing happen as an answer to my question.

Thanks in advance!

Answer 1

Your query is missing a from clause. More importantly, the backticks are incorrect . . . and not needed. And, the proper way is to use join :

SELECT *
FROM table1 JOIN
     table2
     ON table1.id = table2.id
ORDER by table1.name ASC; 

When you have an expression such as `table1.id` in backticks, then it is looking for a column name called exactly that -- with a period in the middle. It is not looking for id in table1 . If you use backticks, then you need to include them around the table name and column name separately:

`table1`.`id`

But, I would suggest not using them and naming tables and columns so they are unnecessary. They are cumbersome to type and awkward to read.