/// <summary>
/// 创建通过主键及值关联的返回数据语句片段。
/// </summary>
/// <param name="unit">内容对象。</param>
/// <param name="target">目标对象。</param>
/// <returns>语句片段。</returns>
internal static SelectFragment SelectReturns(this IContentUnit unit, ISourceFragment target)
{
var data = (ContentBase)unit;
var context = data.GenerateContext;
var select = new SelectFragment(context, target);
select.Members.AddRange(unit.ReturnMembers.Select(a => target.GetMember(a.Metadata)));
select.Where = target.JoinCondition(data.CommitObject, data.Table.Keys);
return(select);
}
/// <summary>
/// 创建通过临时表关联的返回数据语句片段。
/// </summary>
/// <param name="unit">内容对象。</param>
/// <param name="target">目标对象。</param>
/// <param name="temptable">临时表。</param>
/// <returns>语句片段。</returns>
internal static SelectFragment SelectReturns(this IContentUnit unit, ISourceFragment target, TemporaryTableFragment temptable)
{
var data = (ContentBase)unit;
var context = data.GenerateContext;
var select = new SelectFragment(context, target);
select.Members.AddRange(unit.ReturnMembers.Select(a => target.GetMember(a.Metadata)));
select.AddSource(temptable);
target.Join(temptable, data.Table.Keys);
return(select);
}
//生成更新表达式。
private void GenerateForUpdateMembers(GenerateContext context, CommitUnitBase unit, UpdateFragment update, ISourceFragment source)
{
foreach (var member in unit.Members)
{
switch (member.ValueType)
{
case ECommitValueType.Constant:
update.SetValue(member.Metadata, source.GetMember(member.Metadata));
break;
case ECommitValueType.Expression:
var exp = (CommitExpressionMember)member;
update.SetValue(member.Metadata, update.CreateExpression(exp.Expression));
break;
}
}
}
private static void SetCommitMembers(this ContentBase data, UpdateFragment update, CommitUnitBase unit, ISourceFragment source = null)
{
source = source ?? data.CommitObject;
foreach (var member in unit.Members)
{
switch (member.ValueType)
{
case ECommitValueType.Constant:
update.SetValue(member.Metadata, source.GetMember(member.Metadata));
break;
case ECommitValueType.Expression:
var exp = (CommitExpressionMember)member;
update.SetValue(member.Metadata, update.CreateExpression(exp.Expression));
break;
}
}
}
private void WriteFragmentForCommitReturning(SqlWriter writer, List <IMemberFragment> returnMmebers, ISourceFragment target)
{
if (returnMmebers.Any())
{
var command = target.Context.Data.OperateCommand.GetCustomCommand <IOracleCustomCommand>();
writer.Write(" RETURNING ");
returnMmebers.OfType <CommitMemberFragment>().ForEach(
() => writer.Write(','),
m =>
{
var member = target.GetMember(m.Property);
WriteDbName(writer, member.OutputName);
});
writer.Write(" INTO ");
returnMmebers.OfType <CommitMemberFragment>().ForEach(() => writer.Write(','),
m => WriteParameterName(writer, command.AddParameter(m.Metadata)));
}
}
public static InsertFragment Insert(this GenerateContext context, ISourceFragment source, TableMetadata target
, IEnumerable <ColumnMetadata> members)
{
DbName name = null;
if (context.Data is ContentBase data)
{
name = data.TargetName;
}
var table = new TableFragment(context, target, name);
var select = new SelectFragment(context, source);
var current = new InsertFragment(context, table, select);
foreach (var member in members)
{
select.CreateMember(null, source.GetMember(member));
current.CreateMember(null, member);
}
return(current);
}
