Robert, That is how I had originally understood the configuration parameters to work. Thanks.
BTW, Michael sent a reply that I interpreted his meaning to be that the CM configuration could conflict with itself. Your explanation seems to be consistent with how I would expect it to work. Unless I am off track with Michael's response, I feel I understand yours a bit better. Thanks, Joe On Apr 20, 2010, at 4:24 PM, Robert Zeigler wrote: > Cayenne generates the appropriat AUTO_PK_SUPPORT table regardless of the pk > generation strategy, but if your pk generation strategy is "Database > Generated" (AND if your db + driver support auto-pk generation), it won't > actually use it; it will allow the database to generate the id and use the > generated id. > > Robert > > On Tue, Apr 20, 2010 at 9:15 AM, Joe Baldwin <[email protected]>wrote: > >> Michael, >> >> I need a simple verification (because the webhost tech person is very >> confused). >> >> To explain further: I am using Cayenne Modeler to design the entities, and >> to create the database tables in MySQL. (i.e. Tools - Generate Database >> Schema). My understanding, and my tests have proved, if you set [PK >> Generation Strategy] to "Database-Generated", and [Auto Incremented] to "oid >> (INTEGER)" then Cayenne Modeler will "request/instruct/ask " MySQL to create >> a table, then set the oid as the primary key, and set auto_increment to >> "true" for that field. >> >> The following code was generated by the Cayenne Modeler (I deleted >> everything not having to do with the table or key) >> >> CREATE TABLE pickers.product (PRIMARY KEY (oid)) ENGINE=InnoDB; >> CREATE TABLE AUTO_PK_SUPPORT ( TABLE_NAME CHAR(100) NOT NULL, >> NEXT_ID BIGINT NOT NULL, UNIQUE (TABLE_NAME)); >> DELETE FROM AUTO_PK_SUPPORT WHERE TABLE_NAME IN ('product'); >> INSERT INTO AUTO_PK_SUPPORT (TABLE_NAME, NEXT_ID) VALUES ('product', >> 200); >> >> >> The question now is: Has Cayenne Modeler generated SQL that creates a table >> named "product", with a primary key "oid", whose value is automatically >> created by MySQL's InnoDB engine, using auto_increment, at the time of the >> INSERT? Another way of asking this is: In this scenario, does Cayenne >> generate the key, or does MySQL generate the key? >> >> I would like to forward a brief response to the webhost. >> >> Thanks, >> Joe >> >> >> >> >> On Apr 20, 2010, at 9:25 AM, Michael Gentry wrote: >> >>> Hi Joe, >>> >>> Your wording on #2 and #3 was a little curious to me. I don't know if >>> you used Cayenne Modeler to generate your schema or if you are using >>> an existing schema. Cayenne (at runtime) doesn't really instruct the >>> database (MySQL) to auto-generate keys. Cayenne will nont provide a >>> value for "oid" when inserting the record and that essentially >>> instructs MySQL to auto-generate a key. You set this up when you >>> create your product table, for example. The database needs to know >>> that it is responsible for auto-generating the keys -- Cayenne won't >>> tell it at runtime (other than leaving the key out on insert). >>> >>> Maybe I'm a bit off on what you were asking, but it seems like you are >>> expecting Cayenne to tell MySQL to generate the keys when it actually >>> works the other way around: MySQL is supposed to know to generate the >>> key and Cayenne then asks it for the key it generated. >>> >>> mrg >>> >>> PS. BTW, your settings are correct to use the auto-generated key >>> feature in MySQL, just be sure the table was created to auto-generate >>> on your "oid" column. >>> >>> >>> On Mon, Apr 19, 2010 at 8:03 PM, Joe Baldwin <[email protected]> >> wrote: >>>> I apologize for this, but I am being forced to verify a configuration >> that is pretty obvious. >>>> >>>> Please refer to the attached CM configuration panel for an Entity. >>>> >>>> 1. The Primary Key "PK Generation Strategy" is set to >> "Database-Generated". Please verify that this means that the PK Generation >> Strategy is Database Generated. >>>> 2. The Primary Key "Auto Increment" is set to "oid (INTEGER)". Please >> verify that the field being auto-incremented is "oid". >>>> 3. Please verify that (with the DBMS set to MySQL) that the two previous >> parameters instruct MySQL to use its auto_increment feature to create a new >> "oid" value for inserted records. >>>> >>>> Thanks >>>> Joe >>>> >>>> >>>> >> >>
