private bool IsSameProjection(ShorthandProjection shorthandProjection, ColumnOrderByItemSegment orderItem, SelectCommand selectCommand)
{
if (shorthandProjection.GetOwner() == null)
{
throw new ShardingException("shorthandProjection can not found owner");
}
SimpleTableSegment tableSegment = Find(shorthandProjection.GetOwner(), selectCommand);
return(_schemaMetaData.ContainsColumn(tableSegment.GetTableName().GetIdentifier().GetValue(), orderItem.GetColumn().GetIdentifier().GetValue()));
}
/// <summary>
/// 通过元信息获取表名
/// </summary>
/// <param name="columnName"></param>
/// <param name="schemaMetaData"></param>
/// <returns></returns>
private string FindTableNameFromMetaData(string columnName, SchemaMetaData schemaMetaData)
{
foreach (var table in _tables)
{
if (schemaMetaData.ContainsColumn(table.GetTableName().GetIdentifier().GetValue(), columnName))
{
return(table.GetTableName().GetIdentifier().GetValue());
}
}
return(null);
}