Fix supports_multivalues_insert feature name

[devbis]

This PR fixes multivalues insertion feature that was broken due to a typo

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Fixes #<issue_number_goes_here> 🦕

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[jimfulton]

Thanks. It's a shame there wasn't a test to catch this in the first place.

Can you think of a test for this? Maybe looking at the way inserts get generated?

If not, I will. :)

[devbis]

Hey @jimfulton, I would appreciate your help in adding tests.
unfortunately, I don't have enough time at the moment to dive into one more library. Good, that this problem can be easily monkey-patched.
Feel free to close the PR and submit changes under your account as well.
It will help me to avoid cla signing, etc.

[jimfulton]

OK. Created #226 to track.

[jimfulton]

@devbis this doesn't do what I guessed it did. :)

What motivated you to do this -- what breaks without it?

[jimfulton]

Reopening to see if any tests are affected.

[devbis]

@devbis this doesn't do what I guessed it did. :)

What motivated you to do this -- what breaks without it?

Sorry for the delay.
I'm trying to bulk insert with the following code:

session.execute(insert(model).values(list_of_dicts))

I want to make the following insert in SQL

INSERT INTO table VALUES (...), (...), .... (...);

It takes the same time as a single insertion, but I can uploads many items at once.

And without this feature enabled SQLalchemy doesn't allow to do it.

[jimfulton]

Thanks. Hm, that's what I thought too... I'll look some more.