SQLite INSERT 和 DELETE 查询给出错误，但不是 SELECT 查询答案

【问题标题】：SQLite INSERT and DELETE query is giving error, but not SELECt querySQLite INSERT 和 DELETE 查询给出错误，但不是 SELECT 查询
【发布时间】：2021-07-13 07:17:15
【问题描述】：

我正在使用 SQLite(WebSQL) 在我的 Cordova 移动应用程序中本地保存表单数据。
下面的代码适用于同一表的 SELECT 查询，但不适用于 INSERT 或 DELETE 查询。

输出错误为：could not prepare statement

const usersDB = {
    add: function (firstname, lastname, dob, email, phone, city, state, country) {
        databaseHandler.db.readTransaction(
            function (tx) {
                tx.executeSql(
                    "INSERT INTO users(firstname, lastname, dob, email, phone, city, state, country) VALUES(?, ?, ?, ?, ?, ?, ?, ?)",
                    [firstname, lastname, dob, email, phone, city, state, country],
                    function (tx, results) {
                        console.log('User has been saved');
                    },
                    function (tx, error) {
                        console.log('ERROR: Failed to add user', error);
                    }
                );
            }
        );
    },
    selectAll: function (listUsers) {
        databaseHandler.db.readTransaction(
            function (tx) {
                tx.executeSql(
                    "SELECT * FROM users ORDER BY firstname",
                    [],
                    function (tx, results) {
                        listUsers(results);
                    },
                    function (tx, error) {
                        console.log('ERROR: Failed to list users', error);
                    }
                );
            }
        );
    }
}

我搜索了几十个讨论表单，但找不到一个解决此问题的帖子。
我们将不胜感激并提前感谢您的帮助。

【问题讨论】：

标签： javascript sqlite cordova web-sql

【解决方案1】：

读取事务仅用于读取。写事务允许读取和写入。读取事务由 SELECT 语句启动，写入事务由 CREATE、DELETE、DROP、INSERT 或 UPDATE 等语句（统称为“写入语句”）启动。

.readTransaction() 用于只读查询，.transaction() 用于写查询。
所以就我而言，我应该以这种方式使用它们：

const usersDB = {
    add: function (firstname, lastname, dob, email, phone, city, state, country) {
        databaseHandler.db.transaction( // Write mode
            function (tx) {
                tx.executeSql(
                    "INSERT INTO users(firstname, lastname, dob, email, phone, city, state, country) VALUES(?, ?, ?, ?, ?, ?, ?, ?)",
                    [firstname, lastname, dob, email, phone, city, state, country],
                    function (tx, results) {
                        console.log('User has been saved');
                    },
                    function (tx, error) {
                        console.log('ERROR: Failed to add user', error);
                    }
                );
            }
        );
    },
    selectAll: function (listUsers) {
        databaseHandler.db.readTransaction( // read-only mode
            function (tx) {
                tx.executeSql(
                    "SELECT * FROM users ORDER BY firstname",
                    [],
                    function (tx, results) {
                        listUsers(results);
                    },
                    function (tx, error) {
                        console.log('ERROR: Failed to list users', error);
                    }
                );
            }
        );
    }
}

【讨论】：