[Tarantool-discussions] SQL built-in functions position

[Nikita Pettik]

On 27 Sep 18:18, Mergen Imeev wrote:
> Hi all. I have a question that I would like to discuss.
> 
> The question is about SQL built-in functions. At the moment these functions
> are
> partially described in _func and partially in src/box/sql/func.c. I received
> two
> completely different suggestions from my reviewers on what to do with these
> functions:
> 1) Move definitions completely to _func. Remove definitions from func.c.

That's my proposal. It makes name collisions check simple, provides unified
interface to invoke built-in and non-built-in functions, allows to grant
and verify priveleges in the same way and so forth. Built-ins are already
declaraed in _func, so reverting this thing would result in another one
unnecessary schema change and upgrade (so I doubt that implementation would
be somehow 'simpler'). Finally part of functions can turn out to be really
usefull in Lua someday such as date()/time(). So to me the choice is kind
of obvious..

> 2) Move definitions completely to func.c. Remove definitions from _func.
> 
> In the first case, users will be able to see the function definitions. Also,
> in
> the future, we may allow these functions to be called from Lua (although not
> sure if this is necessary). The main idea is 'all functions have the same
> interface'.
> 
> In the second case, the implementation is simpler, and we can more easily
> implement some features, such as "virtual" functions. For users, the
> definition
> can only be seen in the documentation. The main idea is 'SQL built-in
> functions
> are part of SQL'.
> 
> Which of these approaches do you think is more beneficial to us?
>