/// <summary>
/// Provides policy specific query translations. This is where choices about inclusion of related objects and how
/// heirarchies are materialized affect the definition of the queries.
/// </summary>
/// <param name="expression"></param>
/// <returns></returns>
public virtual Expression Translate(Expression expression)
{
// add included relationships to client projection
expression = RelationshipIncluder.Include(this, expression);
expression = UnusedColumnRemover.Remove(expression);
expression = RedundantColumnRemover.Remove(expression);
expression = RedundantSubqueryRemover.Remove(expression);
expression = RedundantJoinRemover.Remove(expression);
// convert any singleton (1:1 or n:1) projections into server-side joins (cardinality is preserved)
expression = SingletonProjectionRewriter.Rewrite(this.mapping.Language, expression);
expression = UnusedColumnRemover.Remove(expression);
expression = RedundantColumnRemover.Remove(expression);
expression = RedundantSubqueryRemover.Remove(expression);
expression = RedundantJoinRemover.Remove(expression);
// convert projections into client-side joins
expression = ClientJoinedProjectionRewriter.Rewrite(this.mapping.Language, expression);
expression = UnusedColumnRemover.Remove(expression);
expression = RedundantColumnRemover.Remove(expression);
expression = RedundantSubqueryRemover.Remove(expression);
expression = RedundantJoinRemover.Remove(expression);
return(expression);
}
/// <summary>
/// Provides policy specific query translations. This is where choices about inclusion of related objects and how
/// heirarchies are materialized affect the definition of the queries.
/// </summary>
/// <param name="expression"></param>
/// <returns></returns>
public virtual Expression Translate(Expression expression)
{
// add included relationships to client projection
var rewritten = RelationshipIncluder.Include(this.Translator.Mapper, expression);
if (rewritten != expression)
{
expression = rewritten;
expression = UnusedColumnRemover.Remove(expression);
expression = RedundantColumnRemover.Remove(expression);
expression = RedundantSubqueryRemover.Remove(expression);
expression = RedundantJoinRemover.Remove(expression);
}
// convert any singleton (1:1 or n:1) projections into server-side joins (cardinality is preserved)
rewritten = SingletonProjectionRewriter.Rewrite(this.Translator.Linguist.Language, expression);
if (rewritten != expression)
{
expression = rewritten;
expression = UnusedColumnRemover.Remove(expression);
expression = RedundantColumnRemover.Remove(expression);
expression = RedundantSubqueryRemover.Remove(expression);
expression = RedundantJoinRemover.Remove(expression);
}
// convert projections into client-side joins
rewritten = ClientJoinedProjectionRewriter.Rewrite(this.Policy, this.Translator.Linguist.Language, expression);
if (rewritten != expression)
{
expression = rewritten;
expression = UnusedColumnRemover.Remove(expression);
expression = RedundantColumnRemover.Remove(expression);
expression = RedundantSubqueryRemover.Remove(expression);
expression = RedundantJoinRemover.Remove(expression);
}
return(expression);
}
internal Expression GetExecutionPlan(Expression expression)
{
LambdaExpression lambda = expression as LambdaExpression;
if (lambda != null)
{
expression = lambda.Body;
}
var translation = expression;
translation = PartialEvaluator.Eval(expression, ExpressionHelper.CanBeEvaluatedLocally);
translation = FunctionBinder.Bind(this, translation);
//translation = PartialEvaluator.Eval(translation, ExpressionHelper.CanBeEvaluatedLocally);
translation = QueryBinder.Bind(ExpressionBuilder, this, translation);
translation = AggregateRewriter.Rewrite(Dialect, translation);
translation = UnusedColumnRemover.Remove(translation);
translation = RedundantColumnRemover.Remove(translation);
translation = RedundantSubqueryRemover.Remove(translation);
translation = RedundantJoinRemover.Remove(translation);
var bound = RelationshipBinder.Bind(ExpressionBuilder, translation);
if (bound != translation)
{
translation = bound;
translation = RedundantColumnRemover.Remove(translation);
translation = RedundantJoinRemover.Remove(translation);
}
translation = ComparisonRewriter.Rewrite(ExpressionBuilder, translation);
var rewritten = RelationshipIncluder.Include(ExpressionBuilder, this, translation);
if (rewritten != translation)
{
translation = rewritten;
translation = UnusedColumnRemover.Remove(translation);
translation = RedundantColumnRemover.Remove(translation);
translation = RedundantSubqueryRemover.Remove(translation);
translation = RedundantJoinRemover.Remove(translation);
}
rewritten = SingletonProjectionRewriter.Rewrite(this.ExpressionBuilder, translation);
if (rewritten != translation)
{
translation = rewritten;
translation = UnusedColumnRemover.Remove(translation);
translation = RedundantColumnRemover.Remove(translation);
translation = RedundantSubqueryRemover.Remove(translation);
translation = RedundantJoinRemover.Remove(translation);
}
rewritten = ClientJoinedProjectionRewriter.Rewrite(this, translation);
if (rewritten != translation)
{
translation = rewritten;
translation = UnusedColumnRemover.Remove(translation);
translation = RedundantColumnRemover.Remove(translation);
translation = RedundantSubqueryRemover.Remove(translation);
translation = RedundantJoinRemover.Remove(translation);
}
//
translation = this.ExpressionBuilder.Translate(translation);
var parameters = lambda != null ? lambda.Parameters : null;
Expression provider = Find(expression, parameters, typeof(InternalDbContext));
if (provider == null)
{
Expression rootQueryable = Find(expression, parameters, typeof(IQueryable));
provider = Expression.Property(rootQueryable, typeof(IQueryable).GetProperty("Provider"));
}
return(ExecutionBuilder.Build(this.Dialect, this, translation, provider));
}