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SCORE ID COMPANYNAME
0.88 6 xabc
0.75 3 abx
0.59 3 xbc
0.59 4 axc
How do I find out if the fuzzy search index is enabled for column x?
See Basic Examples.
How do I enable the fuzzy search index for a particular column?
See Basic Examples.
The additional data structures will increase the total memory footprint of the loaded table. In unfavorable cases
the memory footprint of the column can double.
How can I see how much memory is used for a fuzzy search index?
See Memory Usage [page 267].
Is the score between request and result always stable for TEXT columns?
It depends on how you look at the topic. The algorithm is indeed deterministic, but you need to take all parameters
into account. Cases can be constructed where a small change in the fuzzySimilarity will change the rank between
the same strings.
Why is this? The fuzzySimilarity is the minimum score that tokens need to reach to be considered for the result. If
you use andThreshold or the keyword "OR" in your search, not all tokens have to reach the fuzzySimilarity to be
part of the result. This can lead to a change in the total score if you change the fuzzySimilarity. Let us look at an
example:
DROP TABLE companies;
CREATE COLUMN TABLE companies
(
id INTEGER PRIMARY KEY,
companyname SHORTTEXT(200)
);
INSERT INTO companies VALUES(1, 'aktien gesellschaft');
INSERT INTO companies VALUES(2, 'aktiv gesellschaft');
Important: The similarity between "aktien" and "aktiv" is 0.77.
SAP HANA Developer Guide
Enabling Search
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