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From Mikael <mikael-arons...@telia.com>
Subject Re: cannot make indexes on long varchar?
Date Sat, 01 Dec 2018 14:05:15 GMT
I would think it's because long columns will not work anway (half page 


Indexes are not supported for columns defined on CLOB, BLOB, LONG 
VARCHAR, and XML data types.

If the length of the key columns in an index is larger than half the 
page size of the index, creating an index on those key columns for the 
table fails. For existing indexes, an insert of new rows for which the 
key columns are larger than half of the index page size causes the 
insert to fail.

Avoid creating indexes on long columns. Create indexes on small columns 
that provide a quick look-up to larger, unwieldy data in the row. You 
might not see performance improvements if you index long columns. For 
information about indexes, see /Tuning Java DB/."

Den 2018-12-01 kl. 14:48, skrev Alex O'Ree:
> Is there a particular reason we can't do indexes on long varchar columns?

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