public void Remove(string Name, InputFragment fragment)
{
if (fragment == null)
{
return;
}
if (Name != null)
{
scopeTable.Remove(Name);
}
if (fragment is SelectStatement)
{
Remove((fragment as SelectStatement).From);
}
else if (fragment is JoinFragment)
{
JoinFragment j = fragment as JoinFragment;
Remove(j.Left);
Remove(j.Right);
}
else if (fragment is UnionFragment)
{
UnionFragment u = fragment as UnionFragment;
Remove(u.Left);
Remove(u.Right);
}
}
public override SqlFragment Visit(DbPropertyExpression expression)
{
propertyLevel++;
PropertyFragment fragment = expression.Instance.Accept(this) as PropertyFragment;
fragment.Properties.Add(expression.Property.Name);
propertyLevel--;
// if we are not at the top level property then just return
if (propertyLevel > 0)
{
return(fragment);
}
ColumnFragment column = new ColumnFragment(null, fragment.LastProperty);
column.PropertyFragment = fragment;
InputFragment input = scope.FindInputFromProperties(fragment);
if (input != null)
{
column.TableName = input.Name;
}
// now we need to check if our column name was possibly renamed
if (input is TableFragment)
{
return(column);
}
SelectStatement select = input as SelectStatement;
UnionFragment union = input as UnionFragment;
if (select != null)
{
select.HasDifferentNameForColumn(column);
}
else if (union != null)
{
union.HasDifferentNameForColumn(column);
}
// input is a table, selectstatement, or unionstatement
return(column);
}
public override SqlFragment Visit(DbUnionAllExpression expression)
{
UnionFragment f = new UnionFragment();
Debug.Assert(expression.Left is DbProjectExpression);
Debug.Assert(expression.Right is DbProjectExpression);
SelectStatement left = VisitInputExpressionEnsureSelect(expression.Left, null, null);
Debug.Assert(left.Name == null);
left.Wrap(null);
SelectStatement right = VisitInputExpressionEnsureSelect(expression.Right, null, null);
Debug.Assert(right.Name == null);
right.Wrap(null);
f.Left = left;
f.Right = right;
return(f);
}
public override SqlFragment Visit(DbUnionAllExpression expression)
{
UnionFragment f = new UnionFragment();
Debug.Assert(expression.Left is DbProjectExpression);
Debug.Assert(expression.Right is DbProjectExpression);
SelectStatement left = VisitInputExpressionEnsureSelect(expression.Left, null, null);
Debug.Assert(left.Name == null);
left.Wrap(null);
SelectStatement right = VisitInputExpressionEnsureSelect(expression.Right, null, null);
Debug.Assert(right.Name == null);
right.Wrap(null);
f.Left = left;
f.Right = right;
return f;
}
public void Visit(UnionFragment f)
{
}
public void Visit(UnionFragment f)
{
}
public override SqlFragment Visit(DbApplyExpression expression)
{
DbExpressionBinding inputBinding = expression.Input;
InputFragment input = VisitInputExpression(inputBinding.Expression, inputBinding.VariableName, inputBinding.VariableType);
DbExpressionBinding applyBinding = expression.Apply;
InputFragment apply = VisitInputExpression(applyBinding.Expression, applyBinding.VariableName, applyBinding.VariableType);
SelectStatement select = new SelectStatement(this);
bool isInputSelect = false;
if (!(input is TableFragment))
{
input.Wrap(scope);
isInputSelect = true;
}
apply.Wrap(scope);
select.From = input;
select.Wrap(scope);
if (apply is SelectStatement)
{
SelectStatement applySel = apply as SelectStatement;
foreach (ColumnFragment f in applySel.Columns)
{
SelectStatement newColSelect = new SelectStatement(this);
newColSelect.From = applySel.From;
newColSelect.Where = applySel.Where;
if (isInputSelect)
{
VisitAndReplaceTableName(newColSelect.Where, (input as SelectStatement).From.Name, input.Name, null);
}
newColSelect.Limit = applySel.Limit;
newColSelect.OrderBy = applySel.OrderBy;
newColSelect.Skip = applySel.Skip;
newColSelect.GroupBy = applySel.GroupBy;
newColSelect.IsDistinct = applySel.IsDistinct;
newColSelect.Columns.Add(f);
newColSelect.Wrap(scope);
scope.Add(applySel.From.Name, applySel.From);
ColumnFragment newCol = new ColumnFragment(apply.Name, f.ColumnName);
newCol.Literal = newColSelect;
newCol.PushInput(newCol.ColumnName);
newCol.PushInput(apply.Name);
select.AddColumn(newCol, scope);
if (string.IsNullOrEmpty(newCol.ColumnAlias))
{
newColSelect.Name = newCol.ColumnName;
newCol.ColumnAlias = newCol.ColumnName;
}
scope.Remove(newColSelect);
}
scope.Remove(applySel.From);
scope.Remove(apply);
}
else if (apply is UnionFragment)
{
UnionFragment uf = apply as UnionFragment;
if (uf.Left == null || uf.Right == null)
{
throw new Exception("Union fragment is not properly formed.");
}
var left = uf.Left as SelectStatement;
var right = uf.Right as SelectStatement;
if (left == null || right == null)
{
throw new NotImplementedException();
}
var whereleft = left.Where as BinaryFragment;
var whereright = right.Where as BinaryFragment;
if (whereleft == null || whereright == null)
{
throw new NotImplementedException();
}
LiteralFragment literalFragmentWhere = null;
//checking where left
if (whereleft.Left is ColumnFragment && whereleft.Right is ColumnFragment)
{
// we replace the where part for a dummy one
if (whereright.Left is ColumnFragment && whereright.Right is ColumnFragment)
{
literalFragmentWhere = new LiteralFragment("1 = 1");
}
}
if (literalFragmentWhere == null)
{
throw new NotImplementedException();
}
var leftouterjoin = new JoinFragment();
leftouterjoin.JoinType = Metadata.GetOperator(DbExpressionKind.LeftOuterJoin);
leftouterjoin.Name = apply.Name;
// validating that column fragment on the left matches the name
// for the input fragment
var leftColumnFragment = whereleft.Left as ColumnFragment;
if (leftColumnFragment == null)
{
throw new NotImplementedException();
}
if (!leftColumnFragment.TableName.Equals(input.Name))
{
new NotImplementedException();
}
var conditionJoin = new BinaryFragment();
conditionJoin.Left = whereleft.Left;
//update to the new reference
var newColumnFragment = whereright.Right as ColumnFragment;
if (newColumnFragment != null)
{
newColumnFragment.TableName = uf.Name;
}
conditionJoin.Right = newColumnFragment;
conditionJoin.Operator = whereleft.Operator;
leftouterjoin.Condition = conditionJoin;
(uf.Left as SelectStatement).Where = literalFragmentWhere;
(uf.Right as SelectStatement).Where = literalFragmentWhere;
leftouterjoin.Left = input;
leftouterjoin.Right = uf;
return(leftouterjoin);
}
return(select);
}
public override SqlFragment Visit(DbPropertyExpression expression)
{
propertyLevel++;
PropertyFragment fragment = expression.Instance.Accept(this) as PropertyFragment;
fragment.Properties.Add(expression.Property.Name);
propertyLevel--;
// if we are not at the top level property then just return
if (propertyLevel > 0)
{
return(fragment);
}
ColumnFragment column = new ColumnFragment(null, fragment.LastProperty);
column.PropertyFragment = fragment;
InputFragment input = scope.FindInputFromProperties(fragment);
if (input != null)
{
column.TableName = input.Name;
}
// now we need to check if our column name was possibly renamed
if (input is TableFragment)
{
if (!string.IsNullOrEmpty(input.Name))
{
SelectStatement sf = scope.GetFragment(input.Name) as SelectStatement;
if (sf != null)
{
// Special case: undo alias in case of query fusing
for (int i = 0; i < sf.Columns.Count; i++)
{
ColumnFragment cf = sf.Columns[i];
if (column.ColumnName == cf.ColumnAlias)
{
column.ColumnName = cf.ColumnName;
column.ColumnAlias = cf.ColumnAlias;
column.TableName = input.Name;
return(column);
}
}
}
}
return(column);
}
SelectStatement select = input as SelectStatement;
UnionFragment union = input as UnionFragment;
if (select != null)
{
select.HasDifferentNameForColumn(column);
}
else if (union != null)
{
union.HasDifferentNameForColumn(column);
}
// input is a table, selectstatement, or unionstatement
return(column);
}
