private List <string> ApplyProjection(List <string> records)
{
var outputColumns = new List <string>();
var tableStructure = TableUtils.GetTableColumns(DatabaseName, TableName);
if (AggregateFunctionList.Count == 0)
{
// Select the values of the columns from the record and add them to the output
foreach (var record in records)
{
var outputRecord = "";
var recordSplit = record.Split('#');
foreach (var output in OutputParamsAliasList)
{
outputRecord += recordSplit[tableStructure.IndexOf(output.Item1.Item2)] + "#";
}
// Apply DISTINCT as well
outputRecord = outputRecord.Remove(outputRecord.Length - 1);
if (!outputColumns.Contains(outputRecord))
{
outputColumns.Add(outputRecord);
}
}
}
else
{
// Collect the result of the aggregations => This will always be one row
}
return(outputColumns);
}
private List <string> ApplyWhereConditions(List <string> unfilteredRecords, string tableName)
{
var records = new List <string>();
var groupedConditions = new List <KeyValuePair <string, List <string> > >();
foreach (var condition in WhereConditionsList)
{
if (groupedConditions.Find(elem => elem.Key == condition.Item1.Item2).Value == null)
{
groupedConditions.Add(new KeyValuePair <string, List <string> >(condition.Item1.Item2, new List <string>()));
}
groupedConditions.Find(elem => elem.Key == condition.Item1.Item2).Value.Add(condition.Item2);
}
var tableStructure = TableUtils.GetTableColumns(DatabaseName, tableName);
foreach (var record in unfilteredRecords)
{
if (RecordMatchesCondition(record, tableStructure, groupedConditions))
{
records.Add(record);
}
}
return(records);
}
private List <string> SelectWithTableScan()
{
try
{
var records = new List <string>();
var unfilteredRecords = MongoDB.GetEntireCollection(TableName);
var groupedConditions = new List <KeyValuePair <string, List <string> > >();
foreach (var condition in WhereConditionsList)
{
if (groupedConditions.Find(elem => elem.Key == condition.Item1.Item2).Value == null)
{
groupedConditions.Add(new KeyValuePair <string, List <string> >(condition.Item1.Item2, new List <string>()));
}
groupedConditions.Find(elem => elem.Key == condition.Item1.Item2).Value.Add(condition.Item2);
}
var tableStructure = TableUtils.GetTableColumns(DatabaseName, TableName);
foreach (var indexRecord in unfilteredRecords)
{
var indRec = indexRecord.GetElement("_id").Value + "#" + indexRecord.GetElement("value").Value;
if (RecordMatchesCondition(indRec, tableStructure, groupedConditions))
{
records.Add(indRec);
}
}
return(records);
}
catch (Exception ex)
{
throw ex;
}
}
public override void ParseAttributes()
{
var splitAttributes = Attributes.Split('|');
var selectedTables = new List <string>();
foreach (var selectAttribute in splitAttributes[0].Split('*'))
{
if (selectAttribute != "")
{
SelectJoinInfo.Add(new SelectJoinInfo(selectAttribute));
var leftTable = selectAttribute.Split('#')[0];
var rightTable = selectAttribute.Split('#')[2];
if (!selectedTables.Contains(leftTable))
{
selectedTables.Add(leftTable);
}
if (!selectedTables.Contains(rightTable))
{
selectedTables.Add(rightTable);
}
}
}
for (int idx = 1; idx < splitAttributes.Length; idx++)
{
if (splitAttributes[idx] != "")
{
var newColumnConfig = new SelectRowInfo(splitAttributes[idx]);
SelectConfigList.Add(newColumnConfig);
}
}
ParseSelectConfig();
foreach (var table in selectedTables)
{
SelectedTablesStructure.Add(new Tuple <string, List <string> >(table, TableUtils.GetTableColumns(DatabaseName, table)));
}
}
