public static string GetCurrentValueAndIncrement <T>(string columnName)
{
var dataset = DatasetInfo.Get <T>();
var column = dataset[columnName];
return
($@"SELECT `{column.Name}` FROM `{dataset.Name}` WHERE id = @id FOR UPDATE;
UPDATE `{dataset.Name}`
SET `{column.Name}` = `{columnName}` + 1
WHERE id = @id");
}
private void KeysAndIndexesAreUnder767Bytes(object database)
{
foreach (var property in database.GetType().GetProperties())
{
var type = property.PropertyType;
if (!type.IsGenericType)
{
continue;
}
type = type.GetGenericArguments()[0];
var dataset = DatasetInfo.Get(type);
foreach (var index in dataset.Indexes)
{
var indexLength = 0;
foreach (var member in index.Members)
{
var m = dataset[member.Name];
indexLength += GetLength(m, dataset);
}
if (indexLength > 767)
{
throw new Exception($"table index '{index.Name}' on '{dataset.Name}' exceeds 767 bytes");
}
}
int primaryKeyLength = 0;
foreach (var key in dataset.PrimaryKey)
{
primaryKeyLength += GetLength(key, dataset);
}
if (primaryKeyLength > 767)
{
throw new Exception($"primary key for '{dataset.Name}' exceeds 767 bytes. Was {primaryKeyLength} bytes.");
}
}
}
private Array DeserializeArray(Type elementType, DbValue[] values)
{
var elementModel = DatasetInfo.Get(elementType);
var list = Array.CreateInstance(elementType, values.Length);
var i = 0;
foreach (var value in values)
{
if (value.Kind == DbValueType.M)
{
list.SetValue(((AttributeCollection)value.Value).DeserializeMap(elementModel), i);
}
i++;
}
return(list);
}
private object DeserializeMap(DatasetInfo model)
{
var instance = Activator.CreateInstance(model.Type);
foreach (var attribute in items)
{
var member = model[attribute.Key];
if (member == null)
{
continue;
}
IDbValueConverter converter;
if (DbValueConverterFactory.TryGet(member.Type, out converter))
{
var value = converter.ToObject(attribute.Value, member);
member.SetValue(instance, value);
}
else if (attribute.Value.Kind == DbValueType.M)
{
var map = (AttributeCollection)attribute.Value.Value;
member.SetValue(instance, map.DeserializeMap(DatasetInfo.Get(member.Type)));
continue;
}
else if (member.Type.IsArray)
{
var list = DeserializeArray(member.Type.GetElementType(), (DbValue[])attribute.Value.Value);
member.SetValue(instance, list);
}
}
return(instance);
}
public T As <T>() => As <T>(DatasetInfo.Get <T>());
public static AttributeCollection FromObject(object instance) => FromObject(instance, DatasetInfo.Get(instance.GetType()));