Stuck on Periodic Table Database of FCC RDB challenge

Backend Development
1

So as the title says, I am stuck on periodic table database challenge. I passed all the challenges except these two.

1. You should add the element with atomic number 9 to your database. Its name is Fluorine, symbol is F, mass is 18.998, melting point is -220, boiling point is -188.1, and it's a nonmetal
2.  You should add the element with atomic number 10 to your database. Its name is Neon, symbol is Ne, mass is 20.18, melting point is -248.6, boiling point is -246.1, and it's a nonmetal

My database tables looks like this,

**element table**
 atomic_number | symbol |   name    
---------------+--------+-----------
             1 | H      | Hydrogen
             2 | He     | Helium
             3 | Li     | Lithium
             4 | Be     | Beryllium
             5 | B      | Boron
             6 | C      | Carbon
             7 | N      | Nitrogen
             8 | O      | Oxygen
             9 | F      | Fluorine
            10 | Ne     | Neon

** properties table **
atomic_number | atomic_mass | melting_point_celsius | boiling_point_celsius | type_id 
---------------+-------------+-----------------------+-----------------------+---------
             1 |       1.008 |                -259.1 |                -252.9 |       1
             2 |      4.0026 |                -272.2 |                  -269 |       1
             3 |        6.94 |                180.54 |                  1342 |       2
             4 |      9.0122 |                  1287 |                  2470 |       2
             5 |       10.81 |                  2075 |                  4000 |       3
             6 |      12.011 |                  3550 |                  4027 |       1
             7 |      14.007 |                -210.1 |                -195.8 |       1
             8 |      15.999 |                  -218 |                  -183 |       1
             9 |      18.998 |                  -220 |                -188.1 |       1
            10 |       20.18 |                -248.6 |                -246.1 |       1

as you can see I have added the two rows, and I don’t seem to have made any mistakes. Still can’t pass the tests. How do I pass the tests?

2

Hey @tanjimanim007, when did you first start the project? I just made a change to it this morning (about 5 hours before your post) because of an issue with those two tests. Someone else wasn’t passing those two tests because, except for the atomic_number, the tests were looking for those numbers as strings. If you started the project before I made those changes, try changing the atomic mass and the melting/boiling point to VARCHAR. Here’s the thread with the solution for that user. Let me know if it works.

If you started after I made the changes, then I may have messed something up.

3

I think I started working on this 2 days ago. Okay changing the type of the mentioned columns to see if it works.

4

Thanks! I changed the atomic_mass column type to VARCHAR and it worked.

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