Re: Back-Sql MySQL

["Pierangelo Masarati" <ando@sys-net.it>]

> 	Now I know you all read a lot of posts about this particular
> subject so I'm going to try and make this as easy as possible. I'm sorry
> about having to ask, but I've read everything I could possibly find on
> this subject (which isn't much btw) and I'm still thoroughly confused.
> Let me get the basics out of the way:
> 	First, the reason I MUST install back-sql is because I work at
> an ISP and we have a bandwidth manager (Allot) that uses LDAP Queries in
> order to add users to certain pipes and whatnot. The problem is that our
> user database and rate groups are maintained on a MySQL database. I am a
> 100% newbie when it comes to database management and basically read to
> learn which is why I'm having a problem with this. If anyone knows of a
> better way to go about transferring a MySQL database to BDB or a better
> way to get the Allot box to make LDAP queries to a MySQL database, I'd
> love to hear it.
> 	Now on to the juicy parts. I'm running RedHat 8.0 with OpenLDAP
> 2.1.25. All the MyODBC drivers have been installed (current release) and
> the interaction between the database and ODBC seems to be working just
> fine. I loaded all the test scripts from rdbms_depend/mysql into my
> MySQL database and the tables and information show up. Here's where I
> get stuck because when I go to start slapd -d 5, I get this:
>
> <<snip snip snip>>>
> load_schema_map(): autoadding 'objectClass' and 'ref' mappings
> load_schema_map(): error executing at_query:
> Return code: -1
> Native error code: 1054
> SQL engine state: S0022
> Message: [MySQL][ODBC 3.51 Driver][mysqld-3.23.58-Max]Unknown column
> 'sel_expr_u' in 'field list'
> ==>backsql_free_db_conn()
> backsql_free_db_conn(): closing db connection
> ==>backsql_close_db_conn()
> <==backsql_close_db_conn()
> <==backsql_free_db_conn()
> backsql_db_open(): connection failed, exiting
> backend_startup: bi_db_open(0) failed! (1)
> slapd shutdown: initiated
> ==>backsql_db_close()
> <==backsql_db_close()
> slapd shutdown: freeing system resources.
> ==>backsql_db_destroy()
> ==>backsql_free_db_env()
> <==backsql_free_db_env()
> ==>destroy_schema_map()
> ==>free_oc(): 'inetOrgPerson'
> ==>free_attr(): 'ref'
> <==free_attr()
> ==>free_attr(): 'objectClass'
> <==free_attr()
> <==free_oc()
> <==destroy_schema_map()
> <==backsql_db_destroy()
> slapd stopped.
> connections_destroy: nothing to destroy.
>
> I saw someone post this in this mailing list elsewhere and the response
> was:
>
> "Because metadata in the test is no longer aligned with the code;
> "mysql" test data is not actively maintained, basically because I had no
> time to set up a mysql and test it.  The only rdbms I actively etsted
> and maintained is postgres.  From what I infer, you don't have any sql
> data to present in LDAP form, so you don't really need mysql, you can
> live with postgres as well; or you can update mysql examples according
> to postgres' ones (and sumbit a patch via ITS :)"

I think I recognize myself in the above writing ;)
I confirm all of the above.  I had no chance (read:
time to setup mySQL and to thoroughly test back-sql)
to try it with back-sql; I usually develop it with
PostgreSQL, and sometimes make it run with BM db2
for business.  I know that somebody used to use mySQL
with back-sql; I prayed those people to provide a
patch of the hacking they had to make to either the
code or the examples, but to no avail. I think you
should try the following:
- remove the examples for mySQL;
- use the examples for PostgreSQL, which are the only
  ones "officially" tested (by me :); they'll surely
  need some work: I don't know what support mySQL
  provides for stored procedures, however, as a first
  step, you may safely ignore all of them, and end
  up with a read-only back-sql
- after this short step, we can figure out how to
  write-enable it; only, it is very unlikely that
  anyone can implement a back-sql with complete
  functionality, i.e. able to write an entire
  database from scratch.
- if you have more specific problems, please feel free
  to ask; only, please make you include all the info
  that is required to debug your problem.

If you work carefully (I suggest you use HEAD code
out of a cvs checkout, at least for the examples)
this might be the time we fix mySQL support.

p.

-- 
Pierangelo Masarati
mailto:pierangelo.masarati@sys-net.it