Hendra-
1) Access builds a hidden index on the Foreign Key when you define RI. You can
define another index, and it becomes an "alias" of the hidden one - there's only
one physical index. But the hidden index does subtract from the limit of 15
indexes per table, so defining one you can see in the UI reduces the number of
available indexes further.
2) No.
3) Dropping an index will positively affect performance only when your Append or
Delete operation encompasses tens of thousands of rows. Access does support
primitive forms of DROP INDEX and CREATE INDEX. You can also do these
operations in DAO. See also:
http://office.microsoft.com/en-us/access-help/CH001041016.aspx
John Viescas, author
Microsoft Office Access 2010 Inside Out
Microsoft Office Access 2007 Inside Out
Building Microsoft Access Applications
Microsoft Office Access 2003 Inside Out
SQL Queries for Mere Mortals
http://www.viescas.com/
(Paris, France)
----------------
From: MS_Access_Professionals@yahoogroups.com
[mailto:MS_Access_Professionals@yahoogroups.com] On Behalf Of
agesthahendra@ymail.com
Sent: Saturday, March 31, 2012 8:55 AM
To: MS_Access_Professionals@yahoogroups.com
Subject: [MS_AccessPros] Indexing Fields
Hi Everyone...
I have several questions about indexing...
* Is there any effects if we indexed manually the foreign key
fields..?(the RI is implemented)... i just want to make sure the
fields are indexed because i want to transfer the MDB to Mysql.
* Does Access create index to the field automaticly if we build join in
query design (not in tables relationships window)..?
(the tables are not joined in tables relationships window)
* To make the process faster, do we have to drop the index of an
indexed field before we run Append / Delete query...?
If so, how the syntax to drop and create index (create index with
the type of index ... Duplicate OK or No Duplicate)
Any explanation would be appreciated..thank you
Regards
Hendra
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