public ReturnStatus Delete(Database database, Table table, ICollection<Filter> filters)
{
string databaseFileName = KeyValue.GetDatabaseFileName(database.Name);
var planner = new SimpleExecutionPlanner(database, repository, new List<Selection>(), new List<Join>(), filters);
var rootOperation = planner.GetRootOperation();
var nonKeyColumnNames = table.Columns.Where(c => !table.PrimaryKey.Contains(c.Name)).Select(c => c.Name).ToList();
var metadata = rootOperation.GetMetadata();
var rows = rootOperation.Execute();
ReturnStatus status = new ReturnStatus();
var indexFactory = new IndexFactory(databaseFileName, repository);
var rowsToDelete = new List<string>();
var rowData = new List<KeyValuePair<string, string>>();
foreach (var row in rows)
{
rowsToDelete.Add(row.Key);
rowData.Add(row);
}
foreach (var row in rowsToDelete)
{
// Check foreign key constraints.
foreach (var association in database.GetAssociationsWhereTableIsParent(table.Name))
{
var indexMeta = table.Indexes.Where(i => i.Name.Equals(association.Name)).Single();
var index = indexFactory.GetIndex(indexMeta);
var foreignKey = string.Empty;
if (index.Exists(row))
{
status.ReturnCode = ReturnCode.ForeignKeyConstraintFailed;
status.Message = string.Format("Foreign key constraint check failed, the key [{0}] is referenced in {1}.", row, association.Child);
return status;
}
}
}
foreach (var row in rowData)
{
// Delete unique indexes.
foreach (var uniqueIndex in table.Indexes.Where(i => i.Unique))
{
var index = indexFactory.GetIndex(uniqueIndex);
var columnValues = new List<string>();
foreach (var column in uniqueIndex.IndexMembers)
{
columnValues.Add(KeyValue.Split(row.Value).ElementAt(KeyValue.Split(metadata.Value).ToList().IndexOf(column)));
}
var uniqueKey = KeyValue.Concatenate(columnValues);
index.Delete(uniqueKey);
}
// Delete foreign key indexes.
foreach (var association in database.GetAssociationsWhereTableIsChild(table.Name))
{
var parentTable = database.GetTable(association.Parent);
var indexMeta = parentTable.Indexes.Where(i => i.Name.Equals(association.Name)).Single();
var index = indexFactory.GetIndex(indexMeta);
var foreignKey = string.Empty;
if (table.PrimaryKey.Contains(association.ColumnMappings.Values.First()))
{
foreignKey = KeyValue.Split(row.Key).ElementAt(table.PrimaryKey.IndexOf(association.ColumnMappings.Values.First()));
}
else
{
foreignKey = KeyValue.Split(row.Value).ElementAt(nonKeyColumnNames.IndexOf(association.ColumnMappings.Values.First()));
}
index.Delete(foreignKey, row.Key);
}
}
foreach (var rowToDelete in rowsToDelete)
{
// Delete primary key and data.
repository.Delete(databaseFileName, table.Name, rowToDelete);
}
status.ReturnCode = ReturnCode.Success;
status.Message = string.Format("({0} row(s) affected)", rowsToDelete.Count);
return status;
}
public DataTable Select(Database database, ICollection<Selection> selections, ICollection<Join> joins,
ICollection<Filter> filters)
{
var planner = new SimpleExecutionPlanner(database, repository, selections, joins, filters);
var rootOperation = planner.GetRootOperation();
DataTable result = new DataTable();
var metadata = rootOperation.GetMetadata();
var queryResult = rootOperation.Execute();
// Add header.
List<string> columns = new List<string>();
columns.AddRange(KeyValue.Split(metadata.Value));
columns.AddRange(KeyValue.Split(metadata.Key));
foreach (var item in columns)
{
result.Columns.Add(item, typeof(string));
}
// Add query result.
foreach (var pair in queryResult)
{
List<string> row = new List<string>();
row.AddRange(KeyValue.Split(pair.Value));
row.AddRange(KeyValue.Split(pair.Key));
result.Rows.Add(row.ToArray());
}
return result;
}
