Re: Re: Database Problems

On Sun, Jun 17, 2012 at 8:22 PM, tamouse mailing lists
<[email protected]> wrote:
> On Sun, Jun 17, 2012 at 5:55 PM, Ethan Rosenberg <[email protected]> wrote:
>> At 04:21 PM 6/17/2012, Jim Giner wrote:
>>
>>> "Ethan Rosenberg" <[email protected]> wrote in message
>>> news:[email protected]...
>>> > At 03:30 PM 6/17/2012, Jim Giner wrote:
>>> >>"Ethan Rosenberg" <[email protected]> wrote in message
>>> >>news:[email protected]...
>>> >> > Dear List -
>>> >> >
>>> >>
>>> >> >
>>> >> > The same query in a PHP program will only give me results for MedRec
>>> >> > 10003
>>> >> >
>>> >>
>>> >>why the "where 1" clause?  Do you know what that is for?
>>> > =================
>>> > Dear Jim
>>> >
>>> > Thanks
>>> >
>>> > As I understand, to enable me to concatenate phases to construct a
>>> > query.
>>> >
>>> > The query does work in MySQL fro the terminal.
>>> >
>>> > Ethan
>>> >
>>>
>>> I don't think so.  All it does is return one record.  The where clause
>>> defines what you want returned.  A '1' returns one record, the first one.
>>> #10003
>>>
>>> I wonder why you think "where 1" enables concatenation??  A query (IN
>>> SIMPLE
>>> TERMS PEOPLE) is simply a SELECT ion of fields from a group of tables,with
>>> a
>>> WHERE clause to define the criteria to limit the rows, and an ORDER BY to
>>> sort the result set.  More complex queries can include GROUP BY when you
>>> are
>>> including summary operators such as SUM(fldname) or MAX(fldname), or a
>>> JOIN
>>> clause, or a host of other clauses that make sql so powerful.  In your
>>> case
>>> I think you copied a sample query that (they always seem to be displayed
>>> with a 'where 1' clause) and left the "1" on it.  To summarzie:
>>>
>>> SELECT a.fld1, a.fld2,b.fld1 from table1 as a, table2 as b WHERE a.key
>>> >100
>>> and a.key = b.key ORDER BY a.fld1
>>>
>>> I"m no expert, but hopefully this makes it a little less complex for you.
>>
>> ================
>>
>> This is a suggestion I received from this list -
>> +++++++++++++++++++++
>>>>
>>>> $query = "select * from Intake3 where ";
>>>
>>>
>>> Maybe I missed it, but you need to have a 1 after the where part in your
>>> select.  So...
>>>
>>> $query = "SELECT * FROM Intake3 WHERE 1 ";
>>
>> ++++++++++++++++++++++++++++
>>
>> I must stress that the query works from the terminal, and fails in the PHP
>> code.
>>
>> My question is why?????
>>
>> Ethan
>
> First off, all "where 1" does is make the statement always true. If
> you don't believe that, try this query:
>
> SELECT * FROM Intake3 WHERE 1;
>
> in mysql and contrast with:
>
> SELECT * FROM Intake3;
>
> you should see identical results.
>
> Secondly, you need to look at where you are gathering the return from
> the query. You show:
>
> $result = mysqli_query($cxn,$query);
>
> but you aren't showing us what you do with $result, as in where you
> fetch the rows and process them. I'm dubious that the query is in fact
> only returning one record. But you can check by echoing
> mysqli_num_rows($result). (I think; I never use the procedural
> version, opting to use the object version instead.)

Just to clarify, what Ethan has is not incorrect: the way he's
constructing the where clause requires at least one expression before
the $allowed_fields gets tacked on:

> $query .= " AND ($key  = '$val') ";

Since if even one of those gets appended, there must be an expression
before the first "AND". The 1 merely evaluates to true here, creating
a valid where clause.

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