Re: Programmers toolkit - C api sprintf-like mysql_query()

Lew Pitcher wrote:

> Peter H. Coffin wrote:
>

>> On Sun, 02 Jul 2017 12:26:08 -0400, Lew Pitcher wrote:
>>> I've recently taken up writing some C code to access mysql databases.
>>> One tedious part of that process is the preparation of query statements
>>> (not "prepared statement" queries, however) using program-supplied
>>> values.
>>>
>>> Typically, to me, that means using sprintf() on a query string like
>>>   "INSERT name, number VALUES ('%s',%d) INTO table"
>>> to plug in the program-supplied values, then executing mysql_query() on
>>> the resulting string to actually perform the query.
>>>
>>> Yes, I know that I could use a "prepared statement", but for the code
>>> I'm writing, that would be overkill. However, the
>>> sprintf()/mysql_query() sequence occurs often enough (and there doesn't
>>> seem to be an equivalent mysql_*() api) that I encapsulated it into a
>>> single function.
>> 
>> So you want to do something that's almost exactly like using prepared
>> statements, but doing prepared statements is "overkill"? You're already
>> doing 95% of the (nominal, very small) amount of extra work involved.
>> And prepared statements also address the issue Jerry brings up.
>> 
[Quoted] >> What's "overkill" about using two statements instead of one?

Ghu save me. That's a cut'n'paste error. I meant...

  SELECT COUNT(icmIcnId) FROM icm WHERE icmCallerId = ?;

> Using mysql_query, it takes the following mysql_()* calls to satisfy this
> query (excluding calls to establish the mysql connection or sanitize the
> input)...
>
> mysql_query()
> mysql_store_result()
> mysql_fetch_row()
> mysql_free_result()
>
> Now, looking at the equivalent, in a prepared statement form, I get (and
> please correct me if I am wrong)
>
> mysql_stmt_init()
> mysql_stmt_prepare()
> mysql_stmt_bind() for my selection value
> mysql_stmt_execute()
> mysql_stmt__bind() for my returned data
> mysql_fetch()
>
> I have an additional question: for the returned data mysql_stmt_bind(),
> what buffer_type do I use for an SQL COUNT() value? The manual(s) don't
> say.
>
>
>

-- 
Lew Pitcher
"In Skills, We Trust"
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