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Limitations
The SNIPPET function has the following limitations:
● Only the first search term specified with the CONTAINS predicate is highlighted in the returned text.
● The query result contains only the first hit of the first search term.
● The text excerpt that is displayed with the search term is limited to a string of 12 tokens.
● This function only works on columns of the TEXT data type or columns with a full text index.
HIGHLIGHTED Function
For search queries using the CONTAINS predicate, you can use the function HIGHLIGHTED to return the
content of the found document with your search term highlighted in bold.
Search queries using the HIGHLIGHTED function return the data type NCLOB.
This function uses the following syntax:
SELECT *, HIGHLIGHTED () FROM
WHERE CONTAINS ()
Limitations
The HIGHLIGHTED function has the following limitations:
● Only the first search term specified with the CONTAINS predicate is highlighted in the returned text.
● The query result contains all hits of the first search term.
● This function only works on columns of the TEXT data type or columns with a full text index.
SCORE Function
For search queries using the CONTAINS predicate, you can use the function SCORE to get the score, that means
the relevance, of a record found.
SAP HANA calculates a score based on the following information:
● The relevance or weighting of attributes in a search using the CONTAINS predicate. The relevance of a hit
depends on the weight of the column that caused the hit. You can specify weights when you create the view or
in the CONTAINS predicate.
● Fuzziness in fuzzy search. The more exact a hit is, the higher the score is.
● Text ranking (TF-IDF).
This function uses the following syntax:
SELECT SCORE (),* FROM
WHERE CONTAINS ()
11.2.2 EXACT Search
An exact search returns records only if the search term or search phrase is contained in the table column exactly
as specified. In the SELECT statement of the search query, you can specify the EXACT search type.
In an exact search, the search engine uses the word dictionary and the phrase index to detect the possible
matches. The search engine then checks whether the words appear and use exactly the same spelling.
SAP HANA Developer Guide
Enabling Search
P U B L I C
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