public static IDbSelect Map(
IDbSelect dbSelect, Type returnType,
IModelInfoProvider infoProvider, IDbObjectFactory dbFactory, UniqueNameGenerator nameGenerator)
{
// If the select returns specified columns, it means there is a constructor in Select,
// e.g (.Select(d => new { A = d.ABC }))
// In this case we do not need to add alias to the end result as where will be one in the select
if (dbSelect.Selection.Any(s => !(s is IDbRefColumn)))
{
return(dbSelect);
}
var entityInfo = infoProvider.FindEntityInfo(returnType);
if (!entityInfo.RequirePropertyNameMapping())
{
return(dbSelect);
}
var alias = nameGenerator.GenerateAlias(dbSelect, TranslationConstants.SubSelectPrefix, true);
var newSelectRef = dbFactory.BuildRef(dbSelect, alias);
var newSelect = dbFactory.BuildSelect(newSelectRef);
foreach (var fieldInfo in entityInfo.Columns)
{
var column = dbFactory.BuildColumn(
newSelectRef, fieldInfo.DbName, fieldInfo.ValType, fieldInfo.PropertyName);
newSelect.Selection.Add(column);
}
return(newSelect);
}
private static IDbJoin MakeJoin(IDbSelect ownerSelect, IDbObject tempSelect, IDbObjectFactory dbFactory, UniqueNameGenerator nameGenerator)
{
var joinAlias = nameGenerator.GenerateAlias(ownerSelect, TranslationConstants.SubSelectPrefix);
var joinTo = dbFactory.BuildRef(tempSelect, joinAlias);
return(dbFactory.BuildJoin(joinTo, ownerSelect));
}
protected override Expression VisitConstant(ConstantExpression c)
{
var entityInfo = _infoProvider.FindEntityInfo(c.Type);
if (entityInfo != null)
{
var dbTable = _dbFactory.BuildTable(entityInfo);
var dbRef = _dbFactory.BuildRef(dbTable);
var dbSelect = _dbFactory.BuildSelect(dbRef);
dbRef.Alias = _nameGenerator.GenerateAlias(dbSelect, dbTable.TableName);
_state.ResultStack.Push(dbSelect);
}
else if (!c.Type.IsAnonymouse())
{
var dbConstant = _dbFactory.BuildConstant(c.Value, true);
_state.ResultStack.Push(dbConstant);
}
return(c);
}