mysql WHERE子句不起作用

Question

I would like to select multiple values in where clause but it is not selecting anything.

This is the select query I have:

'SELECT * FROM table WHERE  id IN (4, 5)  ORDER BY id desc'

what am I missing?

Answer 1

Based on your comments, the reason that the query is failing is because the column is a varchar and you are using int values in your IN clause. MySQL does not convert the type if you quote the numbers then your query will work with varchar

http://dev.mysql.com/doc/refman/5.0/en/type-conversion.html

Answer 2

I would imagine your table has no data with id = 4 or id = 5.

Try

 SELECT * FROM table WHERE  id = 4 

Does that return anything either? I would bet no.

Answer 3

为什么不只是

'SELECT * FROM table WHERE (id = '4' OR id= '5') ORDER BY id desc'