protected override Expression VisitPartialUpdate(PartialUpdateCommand update)
{
this.Write("UPDATE ");
this.WriteTableName(update.Table.Name);
this.WriteLine(Indentation.Same);
bool saveHide = this.HideColumnAliases;
this.HideColumnAliases = true;
this.Write("SET ");
for (int i = 0, n = update.Assignments.Count; i < n; i++)
{
ColumnAssignment ca = update.Assignments[i];
if (i > 0)
{
this.Write(", ");
}
this.Visit(ca.Column);
this.Write(" = ");
this.Visit(ca.Expression);
}
if (update.Where != null)
{
this.WriteLine(Indentation.Same);
this.Write("WHERE ");
this.VisitPredicate(update.Where);
}
this.HideColumnAliases = saveHide;
return(update);
}
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 VisitPartialUpdate(PartialUpdateCommand update)
{
var table = (TableExpression)this.Visit(update.Table);
var where = this.Visit(update.Where);
var assignments = this.VisitColumnAssignments(update.Assignments);
return(this.UpdatePartialUpdate(update, table, where, assignments));
}
//protected override Expression VisitInsert(InsertCommand insert)
//{
// return this.BuildExecuteCommand(insert);
//}
//protected override Expression VisitUpdate(UpdateCommand update)
//{
// return this.BuildExecuteCommand(update);
//}
protected override Expression VisitPartialUpdate(PartialUpdateCommand update)
{
var pcmd = update as PartialUpdateCommand;
var table = pcmd.Table;
var where = pcmd.Where;
var assignments = pcmd.Assignments.Where(ca => (ca.Expression as ConstantExpression).Value != null).ToList();
pcmd = this.UpdatePartialUpdate(update, table, where, assignments);
return(this.BuildExecuteCommand(pcmd));
}
public override Expression GetPartialUpdateExpression(MappingEntity entity, Expression instance, LambdaExpression updateCheck, LambdaExpression selector, Expression @else)
{
var tableAlias = new TableAlias();
var table = new TableExpression(tableAlias, entity, this.mapping.GetTableName(entity));
var where = this.GetIdentityCheck(table, entity, instance);
if (updateCheck != null)
{
Expression typeProjector = this.GetEntityExpression(table, entity);
Expression pred = DbExpressionReplacer.Replace(updateCheck.Body, updateCheck.Parameters[0], typeProjector);
where = where.And(pred);
}
var assignments = this.GetColumnAssignments(table, instance, entity, (e, m) => this.mapping.IsUpdatable(e, m));
Expression update = new PartialUpdateCommand(table, where, assignments);
if (selector != null)
{
return(new BlockCommand(
update,
new IFCommand(
this.translator.Linguist.Language.GetRowsAffectedExpression(update).GreaterThan(Expression.Constant(0)),
this.GetUpdateResult(entity, instance, selector),
@else
)
));
}
else if (@else != null)
{
return(new BlockCommand(
update,
new IFCommand(
this.translator.Linguist.Language.GetRowsAffectedExpression(update).LessThanOrEqual(Expression.Constant(0)),
@else,
null
)
));
}
else
{
return(update);
}
}
protected virtual bool ComparePartialUpdate(PartialUpdateCommand x, PartialUpdateCommand y)
{
return(this.Compare(x.Table, y.Table) && this.Compare(x.Where, y.Where) && this.CompareColumnAssignments(x.Assignments, y.Assignments));
}
