SQL Java中：其中name =變量

Question

這是我的代碼：

public static List GetList(String myname) { 
    . 
    . 
    ResultSet result = stmt.executeQuery("SELECT * FROM authors WHERE name = ?"); 
    result.setString(myname); 
} 

我想選擇其中name = MYNAME（MYNAME是函數的輸入）。

我也試過類似：

WHERE name = @myname 

，但它不工作：/

Answer 1

您沒有設置對結果但對聲明值：

PreparedStatement pstmt = connection.prepareStatement("SELECT * FROM authors WHERE name = ?"); 
pstmt.setString(1, myname); 
ResultSet result = pstmt.executeQuery(); 

Answer 2

試試這個：

ResultSet result = stmt.executeQuery("SELECT * FROM authors WHERE name = " + myname); 

Answer 3

嘛，一個更好的方式去是使用PreparedStatement ，以避免SQL Injection： -

PreparedStatement stmt = con.prepareStatement("SELECT * FROM authors WHERE name = ?"); 
stmt.setString(1, myname); 
ResultSet res = stmt.executeQuery(); 

---

然而，僅僅解決您的問題，您可以使用字符串連接： -

stmt.executeQuery("SELECT * FROM authors WHERE name = '" + myname + "'"); 

---

Answer 4

如果我沒有弄錯，最好在這裏準備好陳述：

PreparedStatement stmt = conn.prepareStatement("SELECT * FROM authors WHERE name = ?"); 
stmt.setString(1, myname); 
ResultSet result = stmt.executeQuery();