Index value length (OpenInsight 32-Bit)
At 02 FEB 2005 12:10:12AM Matthew Crozier wrote:
This has probably been discussed before, but I can't find anything.
Some index values can end up as part of keys in the index tree. Is there a practicle limit to the length of index values in a btree index? Are there any characters to be avoided?
Cheers, M@
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At 02 FEB 2005 03:02AM [email protected] wrote:
Well there ARE documented limits on key lengths but these seem to be indicative rather than proscriptive. Most characters should be OK including * although system delimiters should be avoided.
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At 03 FEB 2005 06:16PM Matthew Crozier wrote:
OK - the OI docs suggest that a record key should be no longer than 25 characters. I'm not sure whether this limit is just for data records, or whether it's for any record key including index keys. The OI docs also suggest not to include spaces or asterisks! So I assume this guideline is just for data key components rather than linear hash keys.
Found other forum topics suggesting that problems can occur if record keys are greater than 40 characters.
We have a number of indexes on multi-part index values with an '*' delimiter. We did seem to have a problem with a four part index value with the first part numeric. Some index records and keys would end up just gibberish. Changing the delimiter to '^' seems to have made it behave. This was a while ago though - back in OI 3 days.
Cheers, M@
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