Re: cannot make indexes on long varchar?

[Rick Hillegas]

On 12/1/18 5:48 AM, Alex O'Ree wrote:

Is there a particular reason we can't do indexes on long varchar columns?


You can use VARCHAR(32672) instead of LONG VARCHAR. Then you can create 
indexes on these columns.


Hope this helps,

-Rick

Re: cannot make indexes on long varchar?

[Peter Ondruška]

Not true, you can index such columns but it does not make sense using
standard as Mikael explained. For such follow Using the luceneSupport
optional tool
.


On Sat, 1 Dec 2018 at 14:48, Alex O'Ree  wrote:

> Is there a particular reason we can't do indexes on long varchar columns?
>


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Peter Ondruška

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Re: cannot make indexes on long varchar?

[Mikael]

I would think it's because long columns will not work anway (half page 
size).


"Indexes

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?

cannot make indexes on long varchar?

[Alex O'Ree]

Is there a particular reason we can't do indexes on long varchar columns?