public static string BuildSelectAttributesClause(EntityMetadata entityMetadata, QueryCacheKey.QueryMode queryMode
, SearchRequestDto dto = null)
{
var buffer = new StringBuilder();
if (queryMode == QueryCacheKey.QueryMode.Count)
{
return(CountClause);
}
buffer.AppendFormat("select ");
if (entityMetadata.FetchLimit() != null && queryMode == QueryCacheKey.QueryMode.Sync)
{
buffer.Append(string.Format(" top({0}) ", entityMetadata.FetchLimit()));
}
var attributes = entityMetadata.Attributes(NoCollections) as IList <EntityAttribute>
?? entityMetadata.Attributes(NoCollections).ToList();
var hasProjection = dto != null && dto.ProjectionFields.Count > 0;
if (hasProjection)
{
foreach (ProjectionField field in dto.ProjectionFields)
{
if (field.Name.StartsWith("#"))
{
if (field.Name.StartsWith("#null"))
{
//this way we can map null attributes, that can be used for unions
//see changeunionschema of hapag´s metadata.xml
buffer.AppendFormat("null" + SelectSeparator);
}
//this is an unmapped attribute
continue;
}
var result = LocateAttribute(entityMetadata, attributes, field);
if (!field.Name.Contains('.') && result == null)
{
//this field is not mapped
continue;
}
string aliasAttribute;
if (result != null && result.Item1.Query != null)
{
aliasAttribute = AliasAttribute(entityMetadata, field.Alias, result.Item1, result.Item2);
}
else
{
aliasAttribute = AliasAttribute(entityMetadata, field);
}
buffer.AppendFormat(aliasAttribute + SelectSeparator);
}
}
else
{
for (var i = 0; i < attributes.Count; i++)
{
var entityAttribute = attributes[i];
if (entityAttribute.Name.StartsWith("#null"))
{
//this way we can map null attributes, that can be used for unions
//see changeunionschema of hapag´s metadata.xml
buffer.AppendFormat("null" + SelectSeparator);
}
else
{
var aliasAttribute = AliasAttribute(entityMetadata, entityAttribute);
buffer.AppendFormat(aliasAttribute + SelectSeparator);
}
}
}
return(buffer.ToString().Substring(0, buffer.Length - SelectSeparator.Count()) + " ");
}
