public InExpression(
[NotNull] AliasExpression operand,
[NotNull] SelectExpression subQuery)
{
Check.NotNull(operand, nameof(operand));
Check.NotNull(subQuery, nameof(subQuery));
Operand = operand;
SubQuery = subQuery;
}
public InExpression(
[NotNull] AliasExpression operand,
[NotNull] IReadOnlyList <Expression> values)
{
Check.NotNull(operand, nameof(operand));
Check.NotNull(values, nameof(values));
Operand = operand;
Values = values;
}
public virtual SelectExpression PushDownSubquery()
{
_subqueryDepth++;
var subquery = new SelectExpression(_sqlQueryGeneratorFactory, SystemAliasPrefix + _subqueryDepth);
var columnAliasCounter = 0;
foreach (var expression in _projection)
{
var aliasExpression = expression as AliasExpression;
if (aliasExpression != null)
{
var columnExpression = aliasExpression.TryGetColumnExpression();
if (columnExpression != null &&
subquery._projection.OfType <AliasExpression>()
.Any(ae => ae.TryGetColumnExpression()?.Name == columnExpression.Name))
{
aliasExpression.Alias = "c" + columnAliasCounter++;
}
}
else
{
aliasExpression = new AliasExpression("c" + columnAliasCounter++, expression);
}
subquery._projection.Add(aliasExpression);
}
subquery.AddTables(_tables);
subquery.AddToOrderBy(_orderBy);
subquery.Predicate = Predicate;
subquery._limit = _limit;
subquery._offset = _offset;
subquery._isDistinct = _isDistinct;
subquery._subqueryDepth = _subqueryDepth;
subquery.IsProjectStar = IsProjectStar || !subquery._projection.Any();
_limit = null;
_offset = null;
_isDistinct = false;
Predicate = null;
ClearTables();
ClearProjection();
ClearOrderBy();
AddTable(subquery);
return(subquery);
}
// TODO: Make polymorphic
public virtual Expression UpdateColumnExpression(
[NotNull] Expression expression,
[NotNull] TableExpressionBase tableExpression)
{
Check.NotNull(expression, nameof(expression));
Check.NotNull(tableExpression, nameof(tableExpression));
var aliasExpression = expression as AliasExpression;
var columnExpression = expression as ColumnExpression;
if (columnExpression != null)
{
return(new ColumnExpression(columnExpression.Name, columnExpression.Property, tableExpression));
}
if (aliasExpression != null)
{
var newAliasExpression
= new AliasExpression(
aliasExpression.Alias,
UpdateColumnExpression(aliasExpression.Expression, tableExpression))
{
SourceMember = aliasExpression.SourceMember
};
return(newAliasExpression);
}
switch (expression.NodeType)
{
case ExpressionType.Coalesce:
{
var binaryExpression = (BinaryExpression)expression;
var left = UpdateColumnExpression(binaryExpression.Left, tableExpression);
var right = UpdateColumnExpression(binaryExpression.Right, tableExpression);
return(binaryExpression.Update(left, binaryExpression.Conversion, right));
}
case ExpressionType.Conditional:
{
var conditionalExpression = (ConditionalExpression)expression;
var test = UpdateColumnExpression(conditionalExpression.Test, tableExpression);
var ifTrue = UpdateColumnExpression(conditionalExpression.IfTrue, tableExpression);
var ifFalse = UpdateColumnExpression(conditionalExpression.IfFalse, tableExpression);
return(conditionalExpression.Update(test, ifTrue, ifFalse));
}
}
return(expression);
}
public virtual AliasExpression AddToOrderBy(
[NotNull] string column,
[NotNull] IProperty property,
[NotNull] TableExpressionBase table,
OrderingDirection orderingDirection)
{
Check.NotEmpty(column, nameof(column));
Check.NotNull(property, nameof(property));
Check.NotNull(table, nameof(table));
var columnExpression = new ColumnExpression(column, property, table);
var aliasExpression = new AliasExpression(columnExpression);
if (_orderBy.FindIndex(o => o.Expression.TryGetColumnExpression()?.Equals(columnExpression) ?? false) == -1)
{
_orderBy.Add(new Ordering(aliasExpression, orderingDirection));
}
return(aliasExpression);
}
public virtual int AddToProjection([NotNull] ColumnExpression columnExpression)
{
Check.NotNull(columnExpression, nameof(columnExpression));
var projectionIndex
= _projection
.FindIndex(e =>
{
var ce = e.TryGetColumnExpression();
return(ce?.Property == columnExpression.Property &&
ce?.Type == columnExpression.Type &&
ce?.TableAlias == columnExpression.TableAlias);
});
if (projectionIndex == -1)
{
var aliasExpression = new AliasExpression(columnExpression);
if (Alias != null)
{
var currentAlias = columnExpression.Name;
var uniqueAlias = CreateUniqueProjectionAlias(currentAlias);
if (!string.Equals(currentAlias, uniqueAlias, StringComparison.OrdinalIgnoreCase))
{
aliasExpression.Alias = uniqueAlias;
}
}
projectionIndex = _projection.Count;
_projection.Add(aliasExpression);
IsProjectStar = false;
}
return(projectionIndex);
}
public virtual void AddToOrderBy([NotNull] IEnumerable <Ordering> orderings)
{
Check.NotNull(orderings, nameof(orderings));
foreach (var ordering in orderings)
{
var aliasExpression = ordering.Expression as AliasExpression;
var columnExpression = ordering.Expression as ColumnExpression;
if (aliasExpression != null)
{
var newAlias = new AliasExpression(aliasExpression.Alias, aliasExpression.Expression);
_orderBy.Add(new Ordering(newAlias, ordering.OrderingDirection));
}
else if (columnExpression != null)
{
_orderBy.Add(new Ordering(new AliasExpression(columnExpression), ordering.OrderingDirection));
}
else
{
_orderBy.Add(ordering);
}
}
}
// TODO: Make polymorphic
public virtual Expression UpdateColumnExpression(
[NotNull] Expression expression,
[NotNull] TableExpressionBase tableExpression)
{
Check.NotNull(expression, nameof(expression));
Check.NotNull(tableExpression, nameof(tableExpression));
var aliasExpression = expression as AliasExpression;
var columnExpression = expression as ColumnExpression;
if (columnExpression != null)
{
return new ColumnExpression(columnExpression.Name, columnExpression.Property, tableExpression);
}
if (aliasExpression != null)
{
var newAliasExpression
= new AliasExpression(
aliasExpression.Alias,
UpdateColumnExpression(aliasExpression.Expression, tableExpression))
{
SourceMember = aliasExpression.SourceMember
};
return newAliasExpression;
}
switch (expression.NodeType)
{
case ExpressionType.Coalesce:
{
var binaryExpression = (BinaryExpression)expression;
var left = UpdateColumnExpression(binaryExpression.Left, tableExpression);
var right = UpdateColumnExpression(binaryExpression.Right, tableExpression);
return binaryExpression.Update(left, binaryExpression.Conversion, right);
}
case ExpressionType.Conditional:
{
var conditionalExpression = (ConditionalExpression)expression;
var test = UpdateColumnExpression(conditionalExpression.Test, tableExpression);
var ifTrue = UpdateColumnExpression(conditionalExpression.IfTrue, tableExpression);
var ifFalse = UpdateColumnExpression(conditionalExpression.IfFalse, tableExpression);
return conditionalExpression.Update(test, ifTrue, ifFalse);
}
}
return expression;
}
public virtual void AddToOrderBy([NotNull] IEnumerable<Ordering> orderings)
{
Check.NotNull(orderings, nameof(orderings));
foreach (var ordering in orderings)
{
var aliasExpression = ordering.Expression as AliasExpression;
var columnExpression = ordering.Expression as ColumnExpression;
if (aliasExpression != null)
{
var newAlias = new AliasExpression(aliasExpression.Alias, aliasExpression.Expression);
_orderBy.Add(new Ordering(newAlias, ordering.OrderingDirection));
}
else if (columnExpression != null)
{
_orderBy.Add(new Ordering(new AliasExpression(columnExpression), ordering.OrderingDirection));
}
else
{
_orderBy.Add(ordering);
}
}
}
public virtual AliasExpression AddToOrderBy(
[NotNull] string column,
[NotNull] IProperty property,
[NotNull] TableExpressionBase table,
OrderingDirection orderingDirection)
{
Check.NotEmpty(column, nameof(column));
Check.NotNull(property, nameof(property));
Check.NotNull(table, nameof(table));
var columnExpression = new ColumnExpression(column, property, table);
var aliasExpression = new AliasExpression(columnExpression);
if (_orderBy.FindIndex(o => o.Expression.TryGetColumnExpression()?.Equals(columnExpression) ?? false) == -1)
{
_orderBy.Add(new Ordering(aliasExpression, orderingDirection));
}
return aliasExpression;
}
public virtual int AddToProjection([NotNull] ColumnExpression columnExpression)
{
Check.NotNull(columnExpression, nameof(columnExpression));
var projectionIndex
= _projection
.FindIndex(e =>
{
var ce = e.TryGetColumnExpression();
return ce?.Property == columnExpression.Property
&& ce?.Type == columnExpression.Type
&& ce.TableAlias == columnExpression.TableAlias;
});
if (projectionIndex == -1)
{
var aliasExpression = new AliasExpression(columnExpression);
if (Alias != null)
{
var currentAlias = columnExpression.Name;
var uniqueAlias = CreateUniqueProjectionAlias(currentAlias);
if (!string.Equals(currentAlias, uniqueAlias, StringComparison.OrdinalIgnoreCase))
{
aliasExpression.Alias = uniqueAlias;
}
}
projectionIndex = _projection.Count;
_projection.Add(aliasExpression);
IsProjectStar = false;
}
return projectionIndex;
}
public virtual SelectExpression PushDownSubquery()
{
_subqueryDepth++;
var subquery = new SelectExpression(_sqlQueryGeneratorFactory, SystemAliasPrefix + _subqueryDepth);
var columnAliasCounter = 0;
foreach (var expression in _projection)
{
var aliasExpression = expression as AliasExpression;
if (aliasExpression != null)
{
var columnExpression = aliasExpression.TryGetColumnExpression();
if (columnExpression != null
&& subquery._projection.OfType<AliasExpression>()
.Any(ae => ae.TryGetColumnExpression()?.Name == columnExpression.Name))
{
aliasExpression.Alias = "c" + columnAliasCounter++;
}
}
else
{
aliasExpression = new AliasExpression("c" + columnAliasCounter++, expression);
}
subquery._projection.Add(aliasExpression);
}
subquery.AddTables(_tables);
subquery.AddToOrderBy(_orderBy);
subquery.Predicate = Predicate;
subquery._limit = _limit;
subquery._offset = _offset;
subquery._isDistinct = _isDistinct;
subquery._subqueryDepth = _subqueryDepth;
subquery.IsProjectStar = IsProjectStar || !subquery._projection.Any();
_limit = null;
_offset = null;
_isDistinct = false;
Predicate = null;
ClearTables();
ClearProjection();
ClearOrderBy();
AddTable(subquery);
return subquery;
}
private bool Equals(AliasExpression other) => Equals(_expression, other._expression) && string.Equals(_alias, other._alias);
public virtual int AddToProjection([NotNull] AliasExpression aliasExpression) => AddAliasToProjection(aliasExpression.Alias, aliasExpression.Expression);
private Expression VisitSelectExpression(SelectExpression selectExpression)
{
base.Visit(selectExpression);
if (!RequiresRowNumberPaging(selectExpression))
{
return selectExpression;
}
var subQuery = selectExpression.PushDownSubquery();
foreach (var projection in subQuery.Projection)
{
var alias = projection as AliasExpression;
var column = projection as ColumnExpression;
if (column != null)
{
column = new ColumnExpression(column.Name, column.Property, subQuery);
selectExpression.AddToProjection(column);
continue;
}
column = alias?.TryGetColumnExpression();
if (column != null)
{
column = new ColumnExpression(column.Name, column.Property, subQuery);
alias = new AliasExpression(alias.Alias, column);
selectExpression.AddToProjection(alias);
}
else
{
column = new ColumnExpression(alias.Alias, alias.Expression.Type, subQuery);
selectExpression.AddToProjection(column);
}
}
if (subQuery.OrderBy.Count == 0)
{
subQuery.AddToOrderBy(
new Ordering(new SqlFunctionExpression("@@RowCount", typeof(int)), OrderingDirection.Asc));
}
var columnExpression = new ColumnExpression(RowNumberColumnName, typeof(int), subQuery);
var rowNumber = new RowNumberExpression(columnExpression, subQuery.OrderBy);
subQuery.ClearOrderBy();
subQuery.AddToProjection(rowNumber, false);
Expression predicate = null;
var offset = subQuery.Offset ?? 0;
if (subQuery.Offset.HasValue)
{
predicate = Expression.GreaterThan(columnExpression, Expression.Constant(offset));
}
if (subQuery.Limit.HasValue)
{
var exp = Expression.LessThanOrEqual(columnExpression, Expression.Constant(offset + subQuery.Limit.Value));
if (predicate != null)
{
exp = Expression.AndAlso(predicate, exp);
}
predicate = exp;
}
selectExpression.Predicate = predicate;
return selectExpression;
}
public virtual int AddToProjection([NotNull] AliasExpression aliasExpression)
{
return(AddAliasToProjection(aliasExpression.Alias, aliasExpression.Expression));
}