public override Expression GetMemberExpression(Expression root, MappingEntity entity, MemberInfo member)
{
if (this.mapping.IsAssociationRelationship(entity, member))
{
var relatedEntity = this.mapping.GetRelatedEntity(entity, member);
var projection = this.GetQueryExpression(relatedEntity);
var declaredTypeMembers = this.mapping.GetAssociationKeyMembers(entity, member).ToList();
var associatedMembers = this.mapping.GetAssociationRelatedKeyMembers(entity, member).ToList();
var where = null as Expression;
for (int i = 0, n = associatedMembers.Count; i < n; i++)
{
var equal = this.GetMemberExpression
(
projection.Projector,
relatedEntity,
associatedMembers[i]).Equal(this.GetMemberExpression(root, entity, declaredTypeMembers[i])
);
where = (where != null) ? where.And(equal) : equal;
}
var newAlias = new TableAlias();
var pc = DbColumnProjector.ProjectColumns
(
this.translator.Linguist.Language,
projection.Projector, null,
newAlias,
projection.Select.Alias
);
var aggregator = DbAggregator.GetAggregator(TypeHelper.GetMemberType(member), typeof(IEnumerable <>).MakeGenericType(pc.Projector.Type));
var result = new DbProjectionExpression
(
new DbSelectExpression(newAlias, pc.Columns, projection.Select, where),
pc.Projector, aggregator
);
return(this.translator.Police.ApplyPolicy(result, member));
}
if (root is DbAliasedExpression aliasedRoot && this.mapping.IsColumn(entity, member))
{
return(new DbColumnExpression
(
TypeHelper.GetMemberType(member),
this.GetColumnType(entity, member),
aliasedRoot.Alias,
this.mapping.GetColumnName(entity, member)
));
}
return(DbQueryBinder.BindMember(root, member));
}
protected Expression MakePredicate(Expression e1, Expression e2, IEnumerable <MemberInfo> members, bool negate)
{
var pred = members.Select(m => DbQueryBinder.BindMember(e1, m).Equal(DbQueryBinder.BindMember(e2, m))).Join(ExpressionType.And);
if (negate)
{
pred = Expression.Not(pred);
}
return(pred);
}
public virtual Expression Translate(Expression expression)
{
expression = DbQueryBinder.Bind(this, expression);
expression = DbAggregateRewriter.Rewrite(this.Translator.Linguist.Language, expression);
expression = DbUnusedColumnRemover.Remove(expression);
expression = DbRedundantColumnRemover.Remove(expression);
expression = DbRedundantSubqueryRemover.Remove(expression);
expression = DbRedundantJoinRemover.Remove(expression);
var bound = DbRelationshipBinder.Bind(this, expression);
if (bound != expression)
{
expression = bound;
expression = DbRedundantColumnRemover.Remove(expression);
expression = DbRedundantJoinRemover.Remove(expression);
}
expression = DbComparisonRewriter.Rewrite(this.Mapping, expression);
return(expression);
}
public virtual Expression ApplyMapping(Expression expression)
{
return(DbQueryBinder.Bind(this, expression));
}