Linear Processing

[skalyanaraman]

Hi,
My name is Srini, with Casecentral in San francisco. I have posted questions a lot before. But, I took a break for almost 2 yrs and I am back again.
I have some questions regarding, when texis does linear processing. Could you please tell me for which of the following linear searching is used? Also, it they do index, which ones need post processing?

1. REX expressions
2. fuzzy searches
3. thesaurus
4. Number pattern matches
5. Proximity searches (I think the new version of texis does not use linear searching right, but checking just as much)

Any other searches that would be linear searched?

By the way, we do have metamorph inverted index on our columns that we want to search for.

thanks!!

[mark]

Rex - (/) always linear
rank searches - require metamorph or metamorph inverted index
xpm - (approximate pattern matcher (%)) always linear
thesaurus - unrelated to linear vs indexed
npm (numeric pattern matcher (#)) - always linear
proximity - linear except when doing within N words. In that case it requires a metamorph inverted index.

Having any term that would require linear processing will cause the search to do post processing.

[John]

An index will be used to resolve as much of the query as possible to avoid a linear scan of the entire table unless all search terms require linear search.

[skalyanaraman]

Hi,
I have one more question with the linear processing. It is said above that thesaurus searching is unrelated to linear vs indexed. What does this mean?
If I search for,
"Select DID from tbltest where DOCTEXT like '~test'"
the thesaurus is looked up for the term test, but, doesn't texis have to look up those terms in the table tbltest using linear or index processing?

Thanks for any help!!

[John]

With the index it can look up the synonyms in the index, and does not require post-processing. When searching without an index it will look for all synonyms in the document.