Company not active in shell/SQL, but it's says otherwise

Question

I use company-dabbrev as backend (source: How add company-dabbrev to the Company completion popup?).

When I open sql-mysql, after filling my credentials, I type show databases; one of the databases is information_schema displayed in the buffer.

When I type informatio in the buffer, there is no completion from Company. When I do C-h v company-backends, I see the following:

(company-wsd-mode
(company-edbi :with company-yasnippet)
(company-bbdb :with company-yasnippet)
(company-nxml :with company-yasnippet)
(company-css :with company-yasnippet)
(company-eclim :with company-yasnippet)
(company-semantic :with company-yasnippet)
(company-clang :with company-yasnippet)
(company-xcode :with company-yasnippet)
(company-cmake :with company-yasnippet)
(company-capf :with company-yasnippet)
(company-files :with company-yasnippet)
(company-dabbrev-code company-gtags company-etags company-keywords :with company-yasnippet)
(company-oddmuse :with company-yasnippet)
(company-dabbrev :with company-yasnippet)
(company-yasnippet :with company-yasnippet)
(company-etags :with company-yasnippet)
(company-gtags :with company-yasnippet)
(company-sql :with company-yasnippet))

So Company-dabbrev is listed in the output. But why is there no completion for information-schema in SQL interactive mode buffer, while company-mode is active as minor mode in same buffer and company-dabbrev is listed as backend?