20.3. Querying Free Text Indexes
20.3.1. CONTAINS predicate
Returns TRUE if a free text indexed column matches a text expression.
Syntax
contains_pred: contains (column, expr, opt_or_value ....) opt_or_value: DESCENDING | START_ID ',' scalar_exp | END_ID ',' scalar_exp | SCORE_LIMIT ',' scalar_exp | RANGES ',' variable | OFFBAND column variable: IDENTIFIER
The column must refer to a column for which there exists a free text index. The expr must be a narrow or wide string expression whose syntax matches the rules in 'Text Query Syntax'. The START_ID is the first allowed document ID to be selected by the expression in its traversal order, e.g. least or equal for ascending and greatest or equal for descending. END_ID is the last allowed ID in the traversal order. For descending order the START_ID must be >= END_ID for hits to be able to exist. For ascending order the START_ID must be <= END_ID for hits to be able to exist.
DESCENDING specifies that the search will produce the hit with the greatest ID first, as defined by integer or composite collation. RANGES specifies that the query variable following the RANGES keyword will be bound to the word position ranges of the hits of the expression inside the document. The variable is in scope inside the enclosing SELECT statement.
SCORE_LIMIT specifies a minimum score that hits must have or exceed to be considered matches of the predicate.
OFFBAND specifies that the following column will be retrieved from the free text index instead of the actual table. For this to be possible the column must have been declared as offband with the CLUSTERED WITH option of the CREATE TEXT INDEX statement.
See Also: | |
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The XCONTAINS Predicate . |