/// <summary>
/// Gets all source aliases.
/// </summary>
/// <param name="node">
/// The node.
/// </param>
/// <returns>
/// The aliases.
/// </returns>
public static IEnumerable <string> GetAllSources(Node node)
{
var retriever = new SourceAliasesRetriever();
retriever.Visit(node);
return(retriever.aliases);
}
private SelectQueryPlan CreateSelectQueryPlan([NotNull] SelectFromStatement node)
{
var usedFields = new HashSet <IField>();
var wildcardAliases = new HashSet <string>();
var fieldNames = node.Expressions.Select(f => f.Expression is WildcardSqlExpression ? "*" : f.Alias);
var valueFactory = this.GetValueFactory(node.Expressions, usedFields, wildcardAliases, SourceAliasesRetriever.GetAllSources(node));
var sourceFactory = this.GetSourceFactory(node.Source);
var query = new MultiPartQuery
{
Fields = usedFields,
FilterExpression = this.data.ConvertToLinqExpression(node.Where, false),
OrderByExpressions = node.Orders.Select(o => new OrderByExpression(this.data.ConvertToLinqExpression(o.Expression, false), o.Ascending)),
WildcardAliases = wildcardAliases,
};
var func = valueFactory as ValueFactory;
var queryPlan = func != null
? new SelectQueryPlan(sourceFactory, query, fieldNames, func)
: new SelectQueryPlan(sourceFactory, query, fieldNames, (AsyncValueFactory)valueFactory);
return(queryPlan);
}
