protected override Expression VisitTable(TableExpression table)
{
this.aliases.Add(table.Alias);
return(table);
}
protected PartialUpdateCommand UpdatePartialUpdate(PartialUpdateCommand update, TableExpression table, Expression where, IEnumerable <ColumnAssignment> assignments)
{
if (table != update.Table || where != update.Where || assignments != update.Assignments)
{
return(new PartialUpdateCommand(table, where, assignments));
}
return(update);
}
protected virtual Expression GetInsertResult(MappingEntity entity, Expression instance, LambdaExpression selector, Dictionary <MemberInfo, Expression> map)
{
var tableAlias = new TableAlias();
var tex = new TableExpression(tableAlias, entity, this.mapping.GetTableName(entity));
var aggregator = Aggregator.GetAggregator(selector.Body.Type, typeof(IEnumerable <>).MakeGenericType(selector.Body.Type));
Expression where;
DeclarationCommand genIdCommand = null;
var generatedIds = this.mapping.GetMappedMembers(entity).Where(m => this.mapping.IsPrimaryKey(entity, m) && this.mapping.IsGenerated(entity, m)).ToList();
if (generatedIds.Count > 0)
{
if (map == null || !generatedIds.Any(m => map.ContainsKey(m)))
{
var localMap = new Dictionary <MemberInfo, Expression>();
genIdCommand = this.GetGeneratedIdCommand(entity, generatedIds.ToList(), localMap);
map = localMap;
}
// is this just a retrieval of one generated id member?
var mex = selector.Body as MemberExpression;
if (mex != null && this.mapping.IsPrimaryKey(entity, mex.Member) && this.mapping.IsGenerated(entity, mex.Member))
{
if (genIdCommand != null)
{
// just use the select from the genIdCommand
return(new ProjectionExpression(
genIdCommand.Source,
new ColumnExpression(mex.Type, genIdCommand.Variables[0].QueryType, genIdCommand.Source.Alias, genIdCommand.Source.Columns[0].Name, null),
aggregator
));
}
else
{
TableAlias alias = new TableAlias();
var colType = this.GetColumnType(entity, mex.Member);
return(new ProjectionExpression(
new SelectExpression(alias, new[] { new ColumnDeclaration("", null, map[mex.Member], colType) }, null, null),
new ColumnExpression(TypeHelper.GetMemberType(mex.Member), colType, alias, "", null),
aggregator
));
}
}
where = generatedIds.Select((m, i) =>
this.GetMemberExpression(tex, entity, m).Equal(map[m])
).Aggregate((x, y) => x.And(y));
}
else
{
where = this.GetIdentityCheck(tex, entity, instance);
}
Expression typeProjector = this.GetEntityExpression(tex, entity);
Expression selection = DbExpressionReplacer.Replace(selector.Body, selector.Parameters[0], typeProjector);
TableAlias newAlias = new TableAlias();
var pc = ColumnProjector.ProjectColumns(this.translator.Linguist.Language, selection, null, newAlias, tableAlias);
var pe = new ProjectionExpression(
new SelectExpression(newAlias, pc.Columns, tex, where),
pc.Projector,
aggregator
);
if (genIdCommand != null)
{
return(new BlockCommand(genIdCommand, pe));
}
return(pe);
}
protected virtual Expression VisitTable(TableExpression table)
{
return(table);
}