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WHERE CONTAINS(postcode, '1234', FUZZY(0.5, 'spellCheckFactor=1.0'))
ORDER BY SCORE() DESC;
Fuzzy Search on Text Columns
Text types support a more sophisticated kind of fuzzy search. Texts are tokenized (split into terms) and the fuzzy
comparison is done term by term. For example, when searching with 'SAP', a record such as 'SAP Deutschland AG
& Co. KG' gets a high score, because the term 'SAP' exists in both texts. A record such as 'SAPPHIRE NOW
Orlando' gets a lower score, because 'SAP' is only a part of the longer term 'SAPPHIRE' (3 of 8 characters match).
Fuzzy search on text columns replaces non-fault-tolerant statements such as
SELECT ... FROM documents WHERE doc_content LIKE '% Driethanolamyn %' ...
The following SQL data types are supported:
● TEXT
● SHORTTEXT
● fulltext index
A fulltext index is an additional index structure that can be defined for non-text columns to add text search
features. Supported column types are, for example, NCLOB and NVARCHAR.
It is possible to speed up the fuzzy search by creating data structures called 'fuzzy search indexes', which are
used for a faster calculation of the fuzzy score. These indexes exist in the memory only, so no additional disk
space is needed.
To get the best response times possible, you should enable the fuzzy search indexes for all database columns that
have a high load of fuzzy searches and for all database columns that are used in performance-critical queries.
Fuzzy Search on SQL Type TEXT
A call to contains that references a TEXT column is automatically processed as a text search. In this case, the
mode textsearch=compare and all fuzzy search options are allowed:
CREATE COLUMN TABLE mytable
(
col1 TEXT
);
SELECT score() AS score, * FROM mytable WHERE contains(col1, 'a b',
fuzzy(0.8, 'textsearch=compare'));
Fuzzy Search on SQL Type SHORTTEXT
When a SHORTTEXT column is created, a column of column store type cs_string and a second hidden text
column are created. A call to contains that references the SHORTTEXT column is automatically redirected by the
SAP HANA Developer Guide
Enabling Search
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