如何使用子查詢與PreparedStatements結合使用？

Question

例如我有以下SQL代碼：

SELECT * 
FROM customer c 
WHERE 2 = (SELECT count(*) 
      FROM account a 
      WHERE a.cust_id = c.cust_id); 

我怎樣才能變換SQL語句準備語句命令？

Answer 1

String queryString = " SELECT * FROM customer c"; 
queryString += " WHERE ? = (SELECT count(*) FROM account a WHERE a.cust_id = c.cust_id)"; 

PreparedStatement stmt = connection.prepareStatement(queryString); 
stmt.setInt(1, theCountYouLookFor) // theCountYouLookFor would be 2 in your example