Chapter 5: Writing Full-Text Search Queries

wildcard

The wildcard operator allows you to substitute wildcard characters for part of the item for which you are searching. Table 5-5 describes the wildcard characters and their attributes.

**Table 5-5: Enhanced Full-Text Search engine wildcard characters**
Character	Function	Syntax	Locates
?	Specifies one alphanumeric character. You do not need to include the wildcard operator when you include the question mark in your query. The question mark is ignored in a set ([]) or in an alternative pattern ({}).	’?an’	“ran,” “pan,” “can,” and “ban”
*	Specifies zero or more of any alphanumeric character. You do not need to include the wildcard operator when you include the asterisk in your query; you should not use the asterisk to specify the first character of a wildcard-character string. The asterisk is ignored in a set ([]) or in an alternative pattern ({}).	*’corp’**	“corporate,” “corporation,” “corporal,” and “corpulent”
[]	Specifies any single character in a set. If a word includes a set, you must enclose the word in backquotes (‘‘). Also, there can be no spaces in a set.	<wildcard> ‘c[auo]t‘	“cat,” “cut,” and “cot”
{}	Specifies one of each pattern separated by a comma. If a word includes a pattern, you must enclose the word in backquotes (‘‘). Also, there can be no spaces in a set.	<wildcard> ‘bank{s,er,ing}‘	“banks,” “banker,” and “banking”
^	Specifies one of any character not included in a set. The caret (^) must be the first character after the left bracket ([) that introduces a set.	<wildcard> ‘st[^oa]ck‘	Excludes “stock” and “stack,” but locates “stick” and “stuck”
-	Specifies a range of characters in a set.	<wildcard> ‘c[a-r]t‘	Includes every three-letter word from “cat” to “crt”

To relevance-rank the result set, include the many modifier in the query. See “Operator modifiers”.

For example, the following query searches for documents that include variations of the word “slingshot:”

select t2.copy
from i_blurbs t1, blurbs t2
where t1.id=t2.id 
and t1.index_any = ’"slingshot*"’

score    copy
-----    -----------------------------------------------------------
100    Albert Ringer was born in a trunk to circus parents, but
    another kind of circus trunk played a more important role
    . . .
    gorilla.  "Slingshotting" himself from the ring ropes, 
    . . .

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