> >I try to generate a unique id for each row in a Mysql-InnoDB Table.
> >Because of many deletes I can't use an auto_increment column.
> >After a Mysql restart, the next value for an auto_increment-column is
> >max(auto_increment-column)+1, and I need a really unique id.
> >
> [JS] See if the UUID() function will suit you.
unfortunately I forgot to note that I use statement-based replication, so I
can't use the UUID() function.
> >
> >My first solution looks like this:
> >I use a second table with an auto-increment-column, and add an insert
> >trigger to the first table.
> >The insert trigger adds a row in the second table and uses the
> >last_insert_id() to get the unique value.
> >The (last) row in the second table will never be deleted.
> >Does anybody confirm with this solution?
> >
> >###################################
> >drop table unique_id_messages_1;
> >create table unique_id_messages_1 (id bigint not null unique, subject
> >text);
> >
> >drop table id_sequences_1;
> >create table id_sequences_1 (id bigint not null primary key
> >auto_increment);
> >
> >drop trigger trg_unique_id_messages_1;
> >
> >DELIMITER |
> >
> >create trigger trg_unique_id_messages_1 BEFORE INSERT ON
> >unique_id_messages_1
> >FOR EACH ROW BEGIN
> > insert into id_sequences_1 values ();
> > set NEW.id = (select last_insert_id());
> >END;
> >|
> >DELIMITER ;
> >
> >insert into unique_id_messages_1 (subject) values ("x1");
> >insert into unique_id_messages_1 (subject) values ("x2");
> >insert into unique_id_messages_1 (subject) values ("x3");
> >insert into unique_id_messages_1 (subject) values ("x4");
> >select * from unique_id_messages_1;
> >###################################
> >
> >
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