Hello all.
I'm a new Sqlite user porting a large db for an open source project
from SQL Server.

I have a question regarding whether an index makes sense or will be
used for a certain scenario. Since the table in question is so large
it takes up to 8 hours for me to create new indexes, so I'd like to
see if I can get a best guess before trying.

A little background info:
This is for a GIS system. The Sqlite database is 2+ gigs at the moment.
The table in question has 17,000,000 rows and is performing well so far.
It has a multicolumn index on 4 columns which are always part of the queries.

NAME TYPE DIRP DIRS

There are 2 more columns that make up the rest of the select clause,
but it is an OR statement. A pseudo select clause would look like
this:

NAME='char' and TYPE='char' DIRP='char' DIRS='char' and (ZIPL =int OR ZIPR=int)

Now to the question:
Can/will a multicolumn index (ZIPL,ZIPR) be used for an OR clause?
If so, what if it was part of the other multicolumn index?

Thanks for any guidance!

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