[Dbix-class] Pointless update on a date field

[Richard Jones]

Matt S Trout wrote:
>> All appears to be working fine, but I notice from the debugging SQL that 
>> the date field (dob) is always updated, even though the submitted value 
>> is identical to the stored value of the retrieved record, ie:
>>
>> UPDATE users SET dob = ?, gender = ? WHERE ( id = ? )
>>
>> I assume this is because I am using InflateColumn::DateTime on the date 
>> fields. If I dump $user->last_name I get a scalar, but $user->dob gives 
>> me a complex data structure (the DateTime object?). But I'm not sure why 
>> it is trying to update the date field. Presumably it's harmless, as the 
>> update would silently fail anyway?
> 
> My suspicion would be that your DB isn't sending back the same datetime
> string as is being saved, so the update always -thinks- the data's changed
> even though the column values are equivalent.
> 
> If so, the DateTime::Format::NameOfYourDb module probably needs patching.
> 
> Fancy trying warn $obj->get_column('dob') before+after to see if I'm right?

Result of 2 updates where only a non-date field should have been affected:

PRE: 1934-12-21
POST:1934-12-21

PRE: 1927-09-09
POST:1927-9-9

However, looking again at the docs it's quite possible that I'm not 
using the InflateColumn::DateTime function properly as I don't actually 
call inflate or deflate before updating or after searching (rather using 
my own function to transform dates to/from MySQL format, and/or using 
dob.strftime() function in the templates). Could that have anything to 
do with the inappropriate field update? Meanwhile I'll have a play with 
InflateColumn::DateTime.
-- 
Richard Jones