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Limitations
The TEXT data type has the following search-relevant limitations:
● SQL string searches are not supported.
● The SQL functions CONCAT and JOIN are not supported.
● TEXT columns cannot be converted to other data types.
● Text analysis is not supported.
For TEXT columns, SAP HANA does not support the following SQL expressions:
● HAVING
● WHERE with strings or non-alphanumeric characters
● ORDER BY
● GROUP BY
● Aggregate expressions (COUNT, MIN, MAX, etc.)
● JOIN ON
Changes to TEXT Indexes
TEXT full text indexes are automatically generated and you do not specify names for them; therefore, you cannot
directly manipulate them. However, when you create, alter, or drop a table column, the same change is
automatically applied to the full text index for that column.
By using the ALTER TABLE statement to affect changes on the index, you can alter the following parameters:
● PHRASE INDEX RATIO
● FUZZY SEARCH INDEX
SHORTTEXT(n) Indexes
If the tables in your SAP HANA database contain columns with text strings that are relatively short in length, you
can define those columns with the SHORTTEXT(n) data type. The SHORTTEXT(n) data type enables both SQL
string search and full text search capabilities.
SAP HANA preprocesses the text in the column and stores that preprocessed text as a full text index in a hidden
column attached to the original column. When queried, the text in the full text index returns with the NVARCHAR
data type. The original text is still available; however, search queries are performed, by default, on the text in the
index.
When you create a column table and define a column with the data type SHORTTEXT(n), as in the following
example, a full text index is automatically generated. Whenever new entries are then inserted in the column, the
full text index is automatically and synchronously updated.
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CREATE COLUMN TABLE
(
k int primary key,
P U B L I C
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SAP HANA Developer Guide
Enabling Search