我指的是http://timheuer.com/blog/archive/2012/08/07/updated-how-to-using-sqlite-from-windows-store-apps.aspx和http://wp.qmatteoq.com/using-sqlite-in-your-windows-8-metro-style-applications/
据我所知,sqlite-net
对外键没有很好的支持。因此,我没有创建一个映射到表的类,而是使用以下方式创建表。
public static readonly String PROFILE_TABLE_CREATE = "create table if not exists "
+ PROFILE_TABLE_NAME + "("
+ COLUMN_PROFILE_ID + " integer primary key autoincrement, "
+ COLUMN_TIMESTAMP + " integer not null, "
+ COLUMN_PROFILE_NAME + " text not null, "
+ COLUMN_AGE + " integer not null, "
+ COLUMN_GENDER + " integer not null"
+ ");";
private async void CreateDatabase()
{
SQLiteAsyncConnection conn = new SQLiteAsyncConnection(DATABASE_NAME);
await conn.ExecuteAsync(PROFILE_TABLE_CREATE);
}
现在,我想执行查询。例如,特定表中有多少行?
我可以像read column names from sqlite table windows 8 app一样执行QueryAsync
。但是,我没有要映射到表的类。
在Java中,我可以执行原始查询,如下所示:
String sql = "select count(*) from " + tableName + " where " + HistorySQLiteOpenHelper.COLUMN_FK_TIMESTAMP + " = " + profileTimestamp;
Cursor cursor = database.rawQuery(sql, null);
如何在C#Windows应用商店应用中执行此操作?
答案 0 :(得分:7)
要获得单个值,例如计数,您可以使用ExecuteScalarAsync
:
SQLiteAsyncConnection conn = new SQLiteAsyncConnection(DATABASE_NAME);
int profileCount = await conn.ExecuteScalarAsync<int>("select count(*) from " + PROFILE_TABLE);