How is data captured when using 2 access databases

[Steve]

I have 2 access databases, One the front-end the other the
back-end. Using ODBC to attach the linked tables. My
forms are bound to my tables. Does any one know of
documentation that explains about how the data is used?
I.e. if the whole back-end database worth of data is move
accross the network to the client for the grouping and
sorting and data use functions? Or how does jet handle
that data?

 

[John Vinson]

I.e. if the whole back-end database worth of data is move
accross the network to the client for the grouping and
sorting and data use functions?

It's not that bad. If (as you certainly should) you have indexes on
the fields used for sorting and searching, the *index* - much smaller
than the table - will be sent to the frontend for processing, followed
by the records actually selected.

If you do a full table scan; e.g. searching a non-indexed field, or
using a criterion which cannot take advantage of an index such as

LIKE "*x*"

then yes, the entire table (but not the entire database :-{) ) will
indeed go "down the wire".

 

[Steve]

-----Original Message-----


I have to ask why you are using ODBC to link the tables rather than plain
old Jet table links. If it's because you are planning to migrate to a real
RDBMS, then that does have some implications for the question.

In short, using a database server will reduce the network use noticeably:
all selections and filters happen there and the only stuff that gets
transferred is the text of the SQL and the actual fields and records
returned. Plain Access will transfer pages of mdb file for processing on
the workstation and this can (a) hog bandwidth and (b) makes the whole
thing very susceptible to network errors, with file corruption a
possibility. I have to admit, though, that I don't know how this is
affected by using ODBC rather than jet links.

If the network performance is a worry, you might consider migrating to
MSDE, which is free.

B Wishes


Tim F

.

Is there a Microsfot document that explians what you have
described I need it to show management.