How can I get a random value that gets constant across rows

What I mean is… I need a randomly generated value first, that after it is generated (for row 1), will repeat across N rows… something like column A in the following example

| _A _ | __ B __|
|1234 | abcd123|
|1234 | dtyj54yt||
|1234 | srths234|
|1234 | 78kj6h54|
|1234 | 3653ew6|
|1234 | 948pgh4|
|1234 | 84gn98n|

I found a solution but is too hacky, there should be a way to do this easier.

Solution:

  1. Create a schema A that includes column A
  2. Generate 1 row
  3. Import it as dataset
  4. Create your final schema where you are going to use it… Change the type of the column A as DataSet, refer this field A of that dataset

Also, I would like to be able to get an initial random value, and then add 1 per row sequentially something like

| ____ A ___ |
| 765493265 |
| 765493266 |
| 765493267 |
| 765493268 |
| 765493269 |
| 765493270 |
| 765493271 |

you get the gist