Compound Indices

[JimS]

If I create a compound index on a table with, say, 2 columns in the index,
then join it to another table using both columns, will Access automatically
use the index, or is there some other way I should do that?

 

[MGFoster]

If I create a compound index on a table with, say, 2 columns in the index,
then join it to another table using both columns, will Access automatically
use the index, or is there some other way I should do that?

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Yes. In most RDBMS the first column in the index is usually used as the
main search part of the index. The second column is a "secondary"
index. So make sure the first column is something you'll use a lot - as
JOIN columns or criteria columns.

HTH,
--
MGFoster:::mgf00 <at> earthlink <decimal-point> net
Oakland, CA (USA)
** Respond only to this newsgroup. I DO NOT respond to emails **

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[Jerry Whittle]

To really know if Access uses an index, Google "access showplan". It tells
you how queries are actually run. Always us the results from the second time
a query is run after being created or modified.