在 SQLite 中未创建数据库（找不到文件）[重复]

Question

我在 android studio 中创建了一个名为 memberInfo.db 的数据库。但在设备文件资源管理器中找不到该文件。我正在使用安卓工作室 3.1.3。我附上了我的设备文件浏览器的图像。

DBHelper.java 类

public static final String DATABASE_NAME = "memberInfo.db";

public DBHelper(Context context) {
    super(context, DATABASE_NAME, null, 1);
}

@Override
public void onCreate(SQLiteDatabase sqLiteDatabase) {
    String SQL_CREATE_ENTRIES = "CREATE TABLE " +
            MembersMaster.Members.TABLE_NAME + " (" +
            MembersMaster.Members.COLUMN_NAME_MEMBER_ID + " INTEGER PRIMARY KEY AUTOINCREMENT," +
            MembersMaster.Members.COLUMN_NAME_FULLNAME + " TEXT," +
            MembersMaster.Members.COLUMN_NAME__ADDRESS + " TEXT," +
            MembersMaster.Members.COLUMN_NAME__PHONE + " TEXT," +
            MembersMaster.Members.COLUMN_NAME__EMAIL + "TEXT," +
            MembersMaster.Members.COLUMN_NAME__BIRTHDATE + "TEXT)";

            sqLiteDatabase.execSQL(SQL_CREATE_ENTRIES);

}


@Override
public void onUpgrade(SQLiteDatabase sqLiteDatabase, int i, int i1) {

}
}

MembersMaster.java 类

package com.heisenberg.librarywiz;

import android.provider.BaseColumns;

public final class MembersMaster {

private MembersMaster() {};

public static class Members implements BaseColumns{

    public static final String TABLE_NAME = "members";
    public static final String COLUMN_NAME_MEMBER_ID = "memId";
    public static final String COLUMN_NAME_FULLNAME = "fullname";
    public static final String COLUMN_NAME__ADDRESS ="address";
    public static final String COLUMN_NAME__PHONE ="phone";
    public static final String COLUMN_NAME__EMAIL ="email";
    public static final String COLUMN_NAME__BIRTHDATE ="birthdate";

}

}

Answer 1

在 SQL_CREATE_ENTIRES 中试试这个：

String SQL_CREATE_ENTRIES = "CREATE TABLE " +
        MembersMaster.Members.TABLE_NAME + " (" +
        MembersMaster.Members.COLUMN_NAME_MEMBER_ID + " INTEGER NOT NULL PRIMARY KEY AUTOINCREMENT, " +
        MembersMaster.Members.COLUMN_NAME_FULLNAME + " TEXT, " +
        MembersMaster.Members.COLUMN_NAME__ADDRESS + " TEXT, " +
        MembersMaster.Members.COLUMN_NAME__PHONE + " TEXT, " +
        MembersMaster.Members.COLUMN_NAME__EMAIL + "TEXT, " +
        MembersMaster.Members.COLUMN_NAME__BIRTHDATE + "TEXT);";

你在表达式的末尾留下了分号。

另一个提示：

public static class Members implements BaseColumns{

public static final String TABLE_NAME = "members";
public static final String COLUMN_NAME_MEMBER_ID = BaseColumns._ID; // if you implement BaseColumns, the table IS should use this
public static final String COLUMN_NAME_FULLNAME = "fullname";
public static final String COLUMN_NAME__ADDRESS ="address";
public static final String COLUMN_NAME__PHONE ="phone";
public static final String COLUMN_NAME__EMAIL ="email";
public static final String COLUMN_NAME__BIRTHDATE ="birthdate";

}

对于数据库名称，请尝试仅使用小写字母，例如“member_info.db”。 db 应在以下目录中创建： /data/data/your_package_name/databases/member_info.db 请让我知道它是否有效（或无效......）