一个SQL查询的结果集可以在另一个SQL查询中使用吗？

Question

I have two tables in mySQL db (photoentry and member). When the user logs in, I retrieve all there user details from the member table based on the email they used to login.

String sql = "SELECT * FROM member WHERE email='"+email+"'";

and displayed the results like so:

 <td><b>Member ID: </b></td><td><input type="text" name="id" value="<%=resultSet.getString("id")%>"/> ></td> 

I want to use this member ID to retrieve the photoentry associated with the user. I have tried

String sql = "SELECT * FROM photoentry p where (SELECT id from member m WHERE p.m_ID = m.id AND email='"+email+"'";

How can I retrieve the photoentry associated with the member using the result set of the original query? (I am using JSP)

Answer 1

Please try this.

String sql = "
SELECT p.* FROM photoentry AS p
   INNER JOIN member AS m ON 
   p.member_id = m.id
        WHERE m.email LIKE '"+email+"'";

Answer 2

You can do:

String sql = "
    SELECT * FROM photoentry AS p
        JOIN member AS m ON (p.member_id = m.id)
            WHERE m.email LIKE '"+email+"'";