Question

我按如下方式创建表格：

_id

但是当我尝试插入用户时，我得到以下异常：

android.database.sqlite.SQLiteException：表用户有3列，但提供了2个值（代码1）:,同时编译：INSERT INTO用户VALUES（＆＃39; testuser＆＃39;，＆＃39; textpassword＆＃ 39）

由于AUTOINCREMENT是主键，它为什么期待它？我也试过GridView，但它没有用。

Answer 1

试试这个

 @Override
public void onCreate(SQLiteDatabase db) {
String sql =
        "CREATE TABLE IF NOT EXISTS users (" +
                "_id INTEGER PRIMARY KEY AUTOINCREMENT NOT NULL, " +
                "name TEXT NOT NULL, " +
                "password TEXT NOT NULL);";
db.execSQL(sql);

sql = "INSERT INTO users(name, password) VALUES ('testuser', 'textpassword')";
db.execSQL(sql);
}

AUTOINCREMENT NOT NULL is missing in your insert query which will increase the value of _id field automatically.

Answer 2

您应该指定要插入的值：

sql = "INSERT INTO users(name, password) VALUES ('testuser', 'textpassword')";

无需指定AUTOINCREMENT：On an INSERT, if the ROWID or INTEGER PRIMARY KEY column is not explicitly given a value, then it will be filled automatically with an unused integer, usually one more than the largest ROWID currently in use. This is true regardless of whether or not the AUTOINCREMENT keyword is used.

使用自动增量主键插入表中

2 个答案: