Would this explanation about ROWID make sense?:
Referencing ROWID: If you make references to ROWID but then export your database (using, for example, the ".dump" command of the sqlite shell) and reimport it, all of your ROWIDs will change and your references won't
be right any more. If you use an INTEGER PRIMARY KEY, the ".dump" command will preserve the values and your references will not be broken by the export.
*** IMPORTANT ***: Please note that ROWID columns are always created by SQLite, even if you don't specify it when creating the table via CREATE TABLE. If this is the case and you do something like this:
SELECT * FROM <some table>
the data returned will not include the ROWID columns, since it really isn't part of the schema. It's always safer to include the ROWID column in the CREATE TABLE statement, since you'll always have a chance to display ROWID's contents.
I have copied part of the text from an old posting written by Dr. Hipp.
My questions are:
- if I declare ROWID as INTEGER PRIMARY KEY in the CREATE TABLE statement, would that be enough to guarantee that the ROWID is safely dumped and reimported?
- Or is ROWID *always* rearranged when reimporting?
- If this is the case I guess I would have to create my own unique column (i.e. MyUniqueUID and type INTEGER PRIMARY KEY, right?
- The part that confuses me about Dr. Hipp's statement is this: 'If you use an INTEGER PRIMARY KEY, the ".dump" command will preserve the values and your references will not be broken by the export.': this is the reason I posted my first question above...
Any comments?
Thanks!
-- Tito
