public IEnumerable <IIndexConfig> GetIndexes(ITableConfig table)
{
var columns = new Dictionary <string, PendingIndex>();
var indexes = new List <IIndexConfig>();
foreach (var column in table.Columns)
{
if (column.Property == null)
{
continue;
}
var attribute = column.Property.GetCustomAttribute <IndexAttribute>(true);
if (attribute == null)
{
continue;
}
if (!columns.ContainsKey(attribute.Name))
{
columns[attribute.Name] = new PendingIndex();
}
columns[attribute.Name].Columns.Add(column);
if (attribute.IsFlagsSpecified)
{
columns[attribute.Name].Flags |= attribute.Flags;
}
}
foreach (var key in columns.Keys)
{
var index = Factories.Index.Create(table, IndexConfig.By(columns[key].Columns, columns[key].Flags));
indexes.Add(index);
}
return(indexes);
}
public static IIndexConfig Index(this ITableConfig table, IEnumerable <IColumnConfig> columns, IndexFlags?flags = null)
{
var selector = IndexConfig.By(columns, flags);
var index = table.GetIndex(selector);
if (index == null)
{
index = table.CreateIndex(selector);
}
return(index);
}
public void Configure(IConfig config, ITableConfig table)
{
var index = table.GetIndex(IndexConfig.By(new[] { "Field1", "Field2", "Field3" }));
if (index != null)
{
index.Expression = index.Expression.Combine(
QueryOperator.AndAlso,
index.Columns.Select(column => index.CreateConstraint().With(expression =>
{
expression.Left = expression.CreateColumn(column);
expression.Operator = expression.CreateOperator(QueryOperator.Is);
expression.Right = expression.CreateUnary(QueryOperator.Not, expression.CreateOperator(QueryOperator.Null));
})).ToArray()
);
}
}