mysql select query

My question is very s开发者_运维问答imple, but I can't seem to find the answer on here.

So,

All I want to do is select from two tables at once (with identical column names[id])

I currently have

"SELECT * FROM table1 WHERE id='$id_var'" 

but I also need to check 'table2' aswell. What's the best way to do this without creating a second query? thanks.

Shane

---

  SELECT * FROM table1 WHERE id='$id_var'
  UNION ALL
  SELECT * FROM table2 WHERE id='$id_var'

---

SELECT * FROM table1 WHERE id = '$id_var'
UNION ALL
SELECT * FROM table2 WHERE id = '$id_var'

However the question you should be asking from yourself is why do you have two tables with identical columns in the first place. Sounds like bad database design to me.

---

You could also do this:

SELECT table1.id, table1.x, table2.y 
FROM table1
LEFT JOIN table2 ON table1.id = table2.id
WHERE table1.id = $id;