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Date: Tue, 18 Nov 2003 11:00:51 +0100
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Subject: Sybase "identical field names" feature on sybase_fetch_array()
From: abazan@filnet.es ("Alex")

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Hello, I've been mailing some lists with this issue without any luck. I =
hope this is the right place to post this.

I was recently shocked when I discovered the implementation of Sybase =
"identical fields".

The PHP manual for sybase_fetch_array() reads:

<snip>
Note: When selecting fields with identical names (for instance, in a =
join), the associative indices will have a sequential number prepended. =
See the example for details.
</snip>

I would like to say that I am against implementing these sort of =
repetitive field returns.  If a programmer wants multiple (identically =
named) fields
returned, they can always modify their SQL statement to reflect unique =
field names:

select t1.id as id1, t2.id as id2 from t1,t2

PHP should NOT be mangling field names returned from the database =
driver, it should simply return the name-value of the LAST field of any =
given
name.

However, if this is to be kept in the code, there are a few important =
considerations that should be taken into account regarding the =
implementation:

1st. Upgading PHP. There are loads of cases where you can find in a =
database different tables with some identical field names. I know this =
is poor database design, but sometimes you find that you have to work =
with a design where this occurs. With this new feature on =
sybase_fetch_array() all the code where one just assumed that the =
returned value for field X was from the last table selected, MUST BE =
RE-WRITTEN.

2nd. IMHO, the implementation of this feature is very poor. When you =
have a JOIN over two tables and they have more that one field with the =
same name:

table A:
id
date
user
afield

table B:
id
date
user
bfield

the resulting join will result in

id
date
user
id1
date2
user3
afield
bfield

A single numeric index is incremented for all repetitive fields, making =
it impossible to make it dynamic. (if you made a select using different =
fields
you will get different field names!!!) I suggest correcting this =
implementation to return field names as follows:

id
date
user
id1
date1
user1
afield
bfield

One counter for each repeated field instead of one unique counter for =
ALL fields.

3rd. Last but not least... This is a feature only implemented in Sybase =
library functions, so when creating cross-db applications, it is much
more difficult to implement generic code.

I would appreciate hearing from the PHP Team about this.
Thanks in advance,

Alex

----------------------------
Alex Bazan
abazan at filnet dot es


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