我有一个程序可以检查User模型,并在值不为null时将值添加到准备好的更新语句中,如下所示:
PreparedStatement pst = conn.prepareStatement("UPDATE users SET name=?,email=?,pwd=?,avatar=?,sts=?,bio=?,country=? WHERE uuid=?");
if(this.name != null) pst.setString(1, this.name);
if(this.email != null) pst.setString(2, this.email);
if(this.password != null) pst.setString(3, this.password);
if(this.avatar != null) pst.setString(4, this.avatar);
if(this.status != null) pst.setString(5, this.status);
if(this.bio != null) pst.setString(6, this.bio);
if(this.country != null) pst.setString(7, this.country);
pst.setString(6, this.id);
我面临的问题是,在准备好的语句中不能有未定义的字段。我可以将不想更改的字段设置为等于什么?
答案 0 :(得分:1)
即使具有NULL
值也要添加参数。然后将update
更改为:
UPDATE users
SET name = coalesce(?, name),
email = coalesce(?, email),
. . .
WHERE uuid = ?;