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Posted by Dave on August 3, 2006, 6:56 am
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>> >> Hello all
>> >>
>> >> Is there a yes/no boolean datatype with mySQL? I can't seem to find if
>> > there
>> >> is, and I have used an int type set to 1 or 0 but that breaks some of
> my
>> >> apps that used to use access which does have a yes/no field.
>> >>
>> >> Many thanks
>> >>
>> >> Dave
>> >
>> > That would be type "tinyint" for which the type "bool" is a synonym.
>> > Access doesn't have a special boolean type either. It also uses an
>> > integer
>> > numeric for "yes/no".
>> >
>> > The yes/no true/false is all in the interpretation.
>> > Thomas Bartkus
>> >
>> >
>>
>> When i query an access database which has a yes/no field with vbscript in
>> asp, the return i get is True or False but when I do the same query with
>> mySQL the return is 1 or 0.
>>
>> Is this just the interpretation of the odbc driver or am i
>> misinterpreting
>> it?
>
> I'm guessing it's an interpretation of the DAO or ADO database libraries
> you are using with vbscript.
>
> I presume that when you say "do the same query with mySQL", you are
> referring to the MySQL command line client app. - yes/no ;-)
>
> In MySQL, there is no real "boolean" flag attached to the field.
> Try this:
> SELECT True; # MySQL returns then integer 1
> SELECT False; # MySQL returns the integer 0
>
> The fact is, "True" and "False" are simple constants reflecting the
> integers
> 1 and 0 respectively.
> More specifically, 0 is False and any number<> 0 is True.
> Boolean algebra, Linux, MySQL running under Linux, and (I presume!) MySQL
> running under Windows all follow this convention consistently.
>
> As far as the MySQL command client is concerned, one needs to coerce it to
> display the words "True" or "False"
> SELECT IF(fld<>0, "True", "False")
> or if you prefer:
> SELECT IF(fld<>0, "Yes", "No")
>
> I don't *think* there is any way to get that to happen automatically in
> the
> MySQL command line client the way you can in Access. If you have linked
> tables or pass through queries in Access that are speaking with MySQL
> tables - these will never see a field labeled "boolean". You will have to
> corece the type using the SELECT IF statements shown above.
>
> But - That's a display/user interface issue.
> The logic works exactly the way you would expect.
>
> Thomas Bartkus
>
Thanks for the info Thomas
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