[Lazarus] TSQLQuery: Getting autoincremented ID value after insert (MySQL)

[Michael Van Canneyt]

On Fri, 14 Nov 2014, Marcos Douglas wrote:

> On Fri, Nov 14, 2014 at 10:15 AM, Michael Van Canneyt
> <michael at freepascal.org> wrote:
>>
>>
>> On Fri, 14 Nov 2014, Reimar Grabowski wrote:
>>
>>> On Thu, 13 Nov 2014 13:26:32 -0300
>>> Marcos Douglas <md at delfire.net> wrote:
>>>
>>>> Hi,
>>>> Take a look in Greyhound project: https://github.com/mdbs99/Greyhound
>>>
>>> I did and could not see how it helps.
>>>
>>>> Here you can see an example using "last id":
>>>> https://github.com/mdbs99/Greyhound/blob/master/test/ghsqltest.pas#L285
>>>
>>> Yes, if you are using Greyhound, which I am not.
>>>
>>> So it looks like there's nothing in TSQLQuery that does the job for me.
>>> I now just use another TSQLQuery with the following SQL:
>>>
>>> SELECT LAST_INSERT_ID() AS SomeNameIChoose;
>>>
>>> Seems to work well, reduces the lines of code as I don't have to set
>>> parameters (my primary goal), can be reused for other inserts (being not
>>> table dependent) and took about 1 Minute to implement.
>>
>>
>> Connections for databases that have lastinsertID you can call the method
>> created for this:
>>
>> Function GetInsertID: int64;
>>
>> There is a plan to let SQLDB retrieve the value of some fields fro the DB,
>> but it is not implemented yet.
>
> Hi Michael,
>
> To do that is need to implement a GetInsertID method in all drivers of
> SQLdb and include a code, like bellow, in TSQLQuery.ApplyRecUpdate:

No. Not all SQL engines support lastID. Postgres and Firebird don't.

A more general mechanism is needed.

Michael.