Referencing into several databases in one request

Prefix

One request can address to several databases simultaneously, if location of object is specified by prefix, which is before name of object through colon. Prefix can be

nickname of concrete database (any word, except 'all' and 'default').
One of databases is database, in which user "is" - usernames and passwords of other databases will be taken from it for execution of stored procedures, and also it will be used, if nickname isn't specified.
```
select * from db1:NAME ...
insert   into db2:NAME ...
```

predicate

"all:" is all databases
"default:" is database, in which user "is" (not silent, but forced specification of this database)

insert   into     all:NAME ...
select * from default:NAME ...
select ... where @fld > any (select @f from all:NAME ...

marker - word, meaning all databases consecutively (any two markers never simultaneously mean the same database). Sign "%" is put before marker.

insert into %db1:NAME select * from %db2:NAME;

System table of nicknames

Each database stores all nicknames, known for its users, in system table 'stn' (System Table of Nicknames) for execution of stored procedures and timers.

stn
LocalUserID	RemoteDbNick	RemoteDbDns	DID
101	db1	database.remote.com	31
101	db2		33
105	db1	data.storage.com	34

Replication

After all said, replication of databases by branded programs loss all sense - always it's possible to make it by extension of SQL, described above.

Dmitry Turin

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