Creating Line (MultiLineString) layer out of CSV file

Question

I need to replicate a *.qgs-file that has 4 different layers as shown in the picture below:

The layer that I am currently trying to replicate is the "links" layer. The information of the layer property is as below:

The attribute table of this layer looks like this:

The csv file, which is the source of the layer in question, looks exactly the same with the exception of the last two columns.
I was able to display the layer visualization using the "Points to Path", that comes from the "Processing Toolbox". However, I don't get the same attribute table as shown previously. In addition, it is not that straightforward as I had to manipulate the csv files beforehand.
I created a "To_From" column and created one csv file for "To_From" filled with "to" and one csv file for "To_From" filled with "from". After that, I add both files using "Add>Add Layer>Add Delimited Text Layer". Subsequently, I merge the layers and create a column "order" with 0 for "to" and 1 for "from". Only after this, I am able to use the "Points to Path".
I wonder if there is an alternative way for my current approach in which I am able to get the attribute table attached previously...
I am using QGIS 3.10.5-A Coruña.

oekoplaner · Answer

I'm not sure whethter I understand your question correctly!
But I would try something like the following steps:

Open the csv with "Layer -> Add Layer -> Add Delimited Text Layer" using "No geometry"
Open the File Calculator in the Attribute Table and create a new field with code similar to:
geom_to_wkt( make_line( make_point( "xFrom" , "yFrom" ) , make_point( "xTo" , "yTo" ) ) )
export the table to a csv file
Import the new csv file with "Layer -> Add Layer -> Add Delimited Text Layer" using the new column as wkt-geometry

Good luck!

Taras · Answer

Put eye on the following workflow

Drag&Drop your .csv-file with attributes into QGIS

Deploy a Virtual Layer through Layer > Add Layer > Add/Edit Virtual Layer... to obtain a layer with geometry, i.e. flows.
SELECT *, setsrid(
                  make_line(
                            make_point("X_From","Y_From"),
                            make_point("X_To","Y_To")
                            ),
                  #here use your SRID, e.g. 25833
                  ) 
FROM "test"

Get the Output

Creating Line (MultiLineString) layer out of CSV file

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