SQL：在不知道所有列名的情况下，从连接中的一个表中选择所有值？

Question

Hello there I wonder if the following is possible (in MySQL): There is a simple query joining two tables:

SELECT * FROM `contact_attending_appointment` AS tcon,`contact` AS tget WHERE tcon.appointment_id = 2 AND tget.id = tcon.contact_id;

This query will return the values of both tables - tcon and tget - joined together. However, I want only to have the columns of ONE table.

Basically in SQL you achieve it like this:

SELECT col_1,col_2,...,col_n FROM ...

Or you get all the columns with

SELECT * FROM ...

However I would like to have something like (as I do not know the columns of tget by their names)

SELECT [* from tget] FROM ...

Is there a general solution for this or is this not possible?

Answer 1

SELECT tget.* FROM contact AS tget ...

Answer 2

The question has already been answered by Rafa. But you seem to be learning SQL. The following is a better way of writing your query:

SELECT c.*
FROM `contact_attending_appointment` caa INNER JOIN
     `contact` c
     ON c.id = caa.contact_id 
WHERE caa.appointment_id = 2;

The important changes are:

1. Using proper ANSI join syntax, where the conditions are in the on clause rather than in the where .
2. Using table aliases that are abbreviations for the table name. Someone looking at the query (even you in two months time) will find it easier to follow the logic.