/// <summary>
/// 将时间点有关的SQL条件填充到ConnectiveSqlClauseCollection
/// </summary>
/// <param name="builder"></param>
/// <param name="timePoint"></param>
/// <param name="fieldPrefix">字段前缀。如果是表空间或Schema，不要忘记后面的'.'</param>
public void FillTimePointInBuilder(ConnectiveSqlClauseCollection builder, DateTime timePoint, string fieldPrefix)
{
//输出结果应该是
//VersionStartTime <= getdate() AND (VersionEndTime > getdate() OR VersionEndTime IS NULL)
builder.NullCheck("builder");
string timeString = TSqlBuilder.Instance.DBCurrentTimeFunction;
if (timePoint == DateTime.MinValue && this._UseSimulatedTime && TimePointContext.Current.UseCurrentTime == false)
{
timePoint = TimePointContext.Current.SimulatedTime;
}
if (timePoint != DateTime.MinValue)
{
timeString = TSqlBuilder.Instance.FormatDateTime(timePoint);
}
WhereSqlClauseBuilder sBuilder = new WhereSqlClauseBuilder();
string vsFieldName = JoinFieldName(fieldPrefix, this.VersionStartTimeFieldName);
sBuilder.AppendItem(vsFieldName, timeString, "<=", true);
WhereSqlClauseBuilder eBuilder = new WhereSqlClauseBuilder(LogicOperatorDefine.Or);
string veFieldName = JoinFieldName(fieldPrefix, this.VersionEndTimeFieldName);
eBuilder.AppendItem(veFieldName, timeString, ">", true).AppendItem(veFieldName, "NULL", "IS", true);
builder.LogicOperator = LogicOperatorDefine.And;
builder.Add(sBuilder).Add(eBuilder);
}
protected virtual WhereSqlClauseBuilder PrepareWhereSqlBuilder(T obj, ORMappingItemCollection mapping)
{
WhereSqlClauseBuilder primaryKeyBuilder = ORMapping.GetWhereSqlClauseBuilderByPrimaryKey(obj);
string vsFieldName = GetPropertyFieldName("VersionStartTime", mapping);
if (primaryKeyBuilder.Exists(item => ((SqlClauseBuilderItemIUW)item).DataField == vsFieldName) == false)
{
primaryKeyBuilder.AppendItem(vsFieldName, obj.VersionStartTime);
}
return(primaryKeyBuilder);
}
private string GetJoinedExistedCountSql(IConnectiveSqlClause ownerKeyBuilder, IConnectiveSqlClause existedKeys, ORMappingItemCollection mapping)
{
HashSet <string> fields = MergeFields(ownerKeyBuilder.GetFields(), existedKeys.GetFields());
WhereSqlClauseBuilder builder = new WhereSqlClauseBuilder();
foreach (string field in fields)
{
builder.AppendItem("A." + field, "B." + field, SqlClauseBuilderBase.EqualTo, true);
}
string innerSql = this.GetInnerExistedObjsSql(ownerKeyBuilder, existedKeys, mapping);
string sql = string.Format("SELECT COUNT(1) FROM ({0}) B WHERE {1}", innerSql, builder.ToSqlString(TSqlBuilder.Instance));
return(sql);
}
/// <summary>
/// 得到一个已经存在的记录的临时表
/// </summary>
/// <param name="ownerKeyBuilder"></param>
/// <param name="existedKeys"></param>
/// <param name="mapping"></param>
/// <returns></returns>
private string GetInnerExistedObjsSql(IConnectiveSqlClause ownerKeyBuilder, IConnectiveSqlClause existedKeys, ORMappingItemCollection mapping)
{
ConnectiveSqlClauseCollection connective = new ConnectiveSqlClauseCollection(LogicOperatorDefine.And);
connective.Add(ownerKeyBuilder);
string endTimeFieldName = GetPropertyFieldName("VersionEndTime", mapping);
WhereSqlClauseBuilder veBuilder = new WhereSqlClauseBuilder();
veBuilder.AppendItem(endTimeFieldName, DBTimePointActionContext.MaxVersionEndTime);
connective.Add(veBuilder);
connective.Add(existedKeys);
return(string.Format("SELECT * FROM {0} WHERE {1}", this.GetTableName(default(T), mapping), connective.ToSqlString(TSqlBuilder.Instance)));
}