Android的SQLite的删除查询不工作

问题描述：

以下SQLite的查询不会删除其ID的开头零。

The following sqlite query does not delete IDs which starts with zero.

Android的SQLite表结构

Android Sqlite Table structure

 String CREATE_TABLE_BUS = "CREATE TABLE " + TABLE_BUS + "("
                    + KEY_TID + " INTEGER PRIMARY KEY AUTOINCREMENT,"    
                    + KEY_BUS_NUM + " TEXT,"
                    + KEY_BUS_NAME + " TEXT,"
                    + KEY_FROM + " TEXT,"
                    + KEY_TO + " TEXT,"
                    + KEY_TYPE + " TEXT"
                    + ")";

            db.execSQL(CREATE_TABLE_BUS);

我一直BUS_NUM为文本，而不是为int的某种目的。

I kept BUS_NUM as text and not as int for some purpose.

这是功能我呼吁删除行。

And this is the function I call to delete a row..

        public void Delete_Bus(String bus_num) {
            SQLiteDatabase db = this.getWritableDatabase();

            db.delete(TABLE_BUS, KEY_BUS_NUM+"="+bus_num , null);
              Log.e("deleting bus num", bus_num);

            db.close(); // Closing database connection
        }

这code工作很细，当code不从零开始。

This code works very fine when the code does not start with zero..

它的工作原理为76555，而不是为09877.请告诉我错了我的code

It works for 76555 and not for 09877. Whats wrong with my code

答

本code生成的查询结尾是这样的：

The query generated by this code ends like this:

DELETE FROM BusTable WHERE BusNum = 012345

该数据库将跨preT这是一个数字，而不是字符串。

The database will interpret this as a number, not a string.

在SQL中，字符串必须用引号引起来：

In SQL, strings must be quoted:

DELETE FROM BusTable WHERE BusNum = '012345'

不过，你可以避免通过参数来格式化字符串：

However, you can avoid having to format the string by using a parameter:

db.delete(TABLE_BUS, KEY_BUS_NUM + " = ?", new String[] { bus_num });

Android的SQLite的删除查询不工作

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