Extending Values in Joined Tables with MYSQL
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I currently have a table of concentrations, which are linked to a table of elements. There is a concentration table

    |conc_id|element_id|conc|
and and element table

    |element_id|symbol|
The concentration table only has element_ids for each conc_id that have non-zero concentrations.
What I am trying to do is create a query which will, for each concentration_id, list all the elements in order, with their concentration, regardless of whether they're non-zero or not. I have tried this in a number of increasingly complicated ways (starting with a `RIGHT JOIN`) but this always outputs a NULL conc_id when there is none of that element in it. The output I am looking for is something like this:

    |conc_id|element_id|symbol|conc|
    |1      |1         |H     |1.2 |
    |1      |2         |He    |NULL|
    |1      |3         |Li    |2.3 |
                  ...
    |3      |1         |H     |4.5 |
    |3      |2         |He    |NULL|
    |3      |3         |Li    |NULL|
                  ...
And so on. Is there a way I can do this without having NULL conc_id?

Thanks for any help in advance...