no column names are known and an empty row can't be inserted. If not set tonull, the nullColumnHack parameter provides the name of nullable column name to explicitly insert a NULL into in thecasewhere
If not set to null, the nullColumnHack parameter provides the name of nullable column name to explicitly insert a NULL into in the case where your values is empty. values ContentValues this map contains the initial column values for the row. The keys should be the column names and the ...
no column names are known and an empty row can't be inserted. If not set to null, the nullColumnHack parameter provides the name of nullable column name to explicitly insert a NULL into in the case where your values is empty. valvalues...
SQL doesn't allow inserting a completely empty row without naming at least one column name. If your provided values is empty, no column names are known and an empty row can't be inserted. If not set to null, the nullColumnHack parameter provides the name of nullable column name to explici...
这种情况下,虽然Link在C#是nullable,但是对sqlite是notnullable,所以 插入 var p = new PhotoDetails { Link = null }; db.Insertable(p).ExecuteCommand(); 抛异常 2.修改table,加入[SugarColumn(IsNullable = true)] internal class PhotoDetails { [SugarColumn(IsPrimaryKey = true, IsIdentity = true)]...
column [constraint constraint_name] constraint_type, 表约束级别 column,... [constraint constraint_name] constraint_type (column,...) 表级的约束除not null外都可以。 unique 约束的列可以包含多行NULL值,因为空值被认为不等于任何值。 由于多列上的unique约束的搜索机制,在部分空值组合unique关键字约束的非...
string columnname = item.DbColumnName.ToLower(); //映射字段添加 (字段名,字段名,表名) db.MappingColumns.Add(columnname, columnname, table_name); } db.DbFirst. SettingClassTemplate(old => { string snp = "\r\n "; var sugartable = GetClassTemplate().Replace("{SugarTable}", @$"{snp...
我一开始以为让所有的 SQLite Statement 共用一个(作为静态变数的) nullable OpaquePointer 就可以了,于是我一开始的设计就是让辞典模组在 deinit() 的时候才跑一次「 sqlite3_finalize()」。因为原厂词库是只读的、在 App Bundle 内,所以我将 journal 塞在了运存内。
publicclassUserDbHelperextendsSQLiteOpenHelper{privatestaticUserDbHelper sHelper;privatestaticfinal StringDB_NAME="user_info.db";//数据库名privatestaticfinal intVERSION=1;//版本号//必须实现其中一个构方法publicUserDbHelper(@Nullable Context context,@Nullable String name,@Nullable SQLiteDatabase.CursorFactory...
...nullColumnHack parameter provides the name of nullable column name to explicitly insert a NULL into in the case 82270 微信为什么使用 SQLite 保存聊天记录? SQLite中对布尔字面量和布尔判断的支持现在和其他开源数据库接近,唯一的差距是SQLite不支持is[not] unknown(你可以使用is [not] null来代替)。.....