English 中文(简体)
更新数据库列并填写false
原标题:Update database column and fill with false

我正在尝试更新我的数据库,以添加另一个名为Visible的列。我希望整个列都填充假值。当我运行代码时,它会到达update函数并抛出以下错误:

android.database.sqlite.SQLiteException: no such column: true: UPDATE Themes2 SET Visibility = true;

private static final String TABLE_THEMES_V2 = "Themes2";
public static final String KEY_VISIBLE = "Visibility";

if (oldVersion < 8) {

            db.execSQL("ALTER TABLE " + TABLE_THEMES_V2 + " ADD COLUMN " + KEY_VISIBLE + " text");
            db.execSQL("UPDATE " + TABLE_THEMES_V2 + " SET " + KEY_VISIBLE + " = true;");

            db.setTransactionSuccessful();
        }

有人知道怎么了吗?我很久以前用过这个函数在列中输入“1”。。。

最佳回答

您的KEY_VSIBLE列具有Text数据类型,因此您应该使用以下语法对其进行更新,

db.execSQL("UPDATE " + TABLE_THEMES_V2 + " SET " + KEY_VISIBLE + " =  true ;");

您只是缺少String值中的单反转标记。

您可以尝试的另一种方法如下,将KEY_VSIBLE列设置为整数类型

db.execSQL("ALTER TABLE " + TABLE_THEMES_V2 + " ADD COLUMN " + KEY_VISIBLE + " INTEGER");
db.execSQL("UPDATE " + TABLE_THEMES_V2 + " SET " + KEY_VISIBLE + " = 1;"); // for True
db.execSQL("UPDATE " + TABLE_THEMES_V2 + " SET " + KEY_VISIBLE + " = 0;"); // for False
问题回答

暂无回答




相关问题
what is wrong with this mysql code

$db_user="root"; $db_host="localhost"; $db_password="root"; $db_name = "fayer"; $conn = mysqli_connect($db_host,$db_user,$db_password,$db_name) or die ("couldn t connect to server"); // perform query ...

Users asking for denormalized database

I am in the early stages of developing a database-driven system and the largest part of the system revolves around an inheritance type of relationship. There is a parent entity with about 10 columns ...

Easiest way to deal with sample data in Java web apps?

I m writing a Java web app in my free time to learn more about development. I m using the Stripes framework and eventually intend to use hibernate and MySQL For the moment, whilst creating the pages ...

join across databases with nhibernate

I am trying to join two tables that reside in two different databases. Every time, I try to join I get the following error: An association from the table xxx refers to an unmapped class. If the ...

How can I know if such value exists in database? (ADO.NET)

For example, I have a table, and there is a column named Tags . I want to know if value programming exists in this column. How can I do this in ADO.NET? I did this: OleDbCommand cmd = new ...

Convert date to string upon saving a doctrine record

I m trying to migrate one of my PHP projects to Doctrine. I ve never used it before so there are a few things I don t understand. In my current code, I have a class similar to this: class ...

热门标签