public AlgebraNodeTree(Table t, string[] projections, string[] selections)
{
head = new AlgebraNode(t, "pure");
if (selections.Length > 0)
{
foreach (string selection in selections)
{
var algebraNode = head;
AlgebraNode n = new AlgebraNode(RelationalAlgebraModule.Selection, new [] { selection }, algebraNode);
head = n;
}
}
if (projections.Length > 0)
{
var algebraNode = head;
AlgebraNode p = new AlgebraNode(RelationalAlgebraModule.Projection, projections, algebraNode);
head = p;
}
PrintTree();
successfulParse = true;
}
public AlgebraNodeTree(Database db, string[] projections, string[] selections, string tableInfo)
{
successfulParse = false;
Parser joinParser = new Parser(tableInfo, Parser.ReadOptions.STRING);
ParseTree joinInfoTree = new ParseTree(joinParser.ParseJoinInfoFull);
Dictionary <string, AlgebraNode> nameToAlgebraNode = new Dictionary <string, AlgebraNode>();
if (joinInfoTree.successfulParse) // creates join tree, unless there are no joins
//joinInfoTree.PrintTree();
{
List <ParseNode> tableNames = joinInfoTree.GetAllOfType("<table_name>");
Table[] tables = new Table[tableNames.Count];
int index = 0;
foreach (ParseNode tableName in tableNames)
{
string name = tableName[0][0].Data;
Table tb;
if (CommandInterpreter.variables.ContainsKey(name))
{
tb = CommandInterpreter.variables[name].Data as Table;
}
else
{
tb = db[name];
}
tables[index] = tb;
if (tables[index] == null)
{
return;
}
index++;
}
foreach (Table table in tables)
{
nameToAlgebraNode.Add(table.Name, new AlgebraNode(table));
}
AlgebraNode fixedJoins =
ConvertJoinInfoFullIntoMultiplesJoinInfoString(joinInfoTree.Head, nameToAlgebraNode);
if (fixedJoins == null)
{
return;
}
head = fixedJoins;
}
else
{
Table tb;
if (CommandInterpreter.variables.ContainsKey(tableInfo))
{
tb = CommandInterpreter.variables[tableInfo].Data as Table;
}
else
{
tb = db[tableInfo];
}
if (tb == null)
{
return;
}
head = new AlgebraNode(tb, "pure");
}
head.PrintTree();
head.EnforceParenthood();
if (selections.Length > 0)
{
foreach (string selection in selections)
{
var algebraNode = head;
Regex namedSelectionStyle = new Regex("\\w*\\.\\w*=\"?\\w*\"?");
if (namedSelectionStyle.IsMatch(selection))
{
string tableName = selection.Split('.')[0];
var originalNode = nameToAlgebraNode[tableName];
var originalParent = originalNode.Parent;
AlgebraNode n = new AlgebraNode(RelationalAlgebraModule.Selection, new [] { selection }, originalNode);
originalParent.ReplaceChild(originalNode, n);
//originalNode.Options = new []{"pure"};
originalParent.PrintTree();
}
else
{
AlgebraNode n = new AlgebraNode(RelationalAlgebraModule.Selection, new [] { selection }, algebraNode);
head = n;
}
head.PrintTree();
}
}
if (projections.Length > 0)
{
var algebraNode = head;
AlgebraNode p = new AlgebraNode(RelationalAlgebraModule.Projection, projections, algebraNode);
head = p;
}
PrintTree();
successfulParse = true;
}
