Hi

Is there way to Join ValueTables? For example

In 1. ValueTable exist 300 000 rows.
In 2. ValueTable exist 200 000 rows.

The Colums are same in each valuetable. In result ValueTable must be 500 000 rows.

Is there way to join those valuetables without iterating each row and adding one by one?

I would suggest to save them in InformationRegister and then make a dynamic query to it.

Why there exist an VT with this quantity of records?

Indeed the task is to get data from Excel document (The rows in document minimum 500 000).

1. We decided to work so: Using Ctrl+C and Ctrl+V we copy 500 000 rows to SpreadSheet documents in few seconds. Then in background job (in RAM) we iterate each row in spreadsheet document. To lower the time spend we separate in some more backgroundjobs that work in same time. from that backgrounds we recieve valuetables (for example in 10 quantity). For some reasons we have to keep data in tabularsection and relative this document with registers. For types formdatacollection and tabularsection we can only use one ValueTable for using Load(<ValueTable>) method. So in our solution, we need to join valuetables.

2. For this task may be outher solutions. If you have any, I'll to it into consideration.

I would save the data in CSV , get the data by batches and then store them into register with an extra  dimension as a reference you mentioned. Then if it is necessary you can filter the values you want to see.

Also you could save all your tabular sections (10) and then make a query to document tabular section filtering by doc ref. No matter which one you use it is not very handy to scroll through 500 000 rows.

Just for information: Platform does not support more than 100.000 rows in one tabular section.

The import of large amount of data is usually made at night time. You can import it into the information register, as Alexey suggested above and process the data in the information register after the import is finished. The flag of import state you can keep in a catalog and separate data in the information register by specifying a reference to the catalog item as a dimension.