If a qualifier is not specified for a homograph in a broader term query, the query expands to include the broader terms of all the homographic terms. Specify a qualifier for term, if term is a homograph (word or phrase with multiple meanings, but the same spelling) that appears in two or more nodes in the same hierarchy branch of thes. The number of broader terms included in the expansion is determined by the value for level. You cannot specify expansion operators in the term argument. For example, if you specify BTG(dog), the expansion includes only those terms that are defined as broader term generic for dog. Oracle Text expands term to include the broader term entries defined for the term in the thesaurus specified by thes. Specify the operand for the broader term operator. (No document scores in the second range, because any document with Brazil in it will be considered to match at least three query terms.)Įxpands a query to include the term defined in the thesaurus as a broader term for term.īTG( term)Įxpands a query to include all terms defined in the thesaurus as broader generic terms for term.īTP( term)Įxpands a query to include all the terms defined in the thesaurus as broader partitive terms for term.īTI( term)Įxpands a query to include all the terms defined in the thesaurus as broader instance terms for term. The first Brazil-and-soccer example document shown above scores in the first range (1-25), the second scores in the third range (51-75), and the third scores in the fourth range (76-100). Because each query term Brazil is considered independent, the entire query is scored as though it has four terms, not two, and thus has four scoring ranges. Note that a query of soccer ACCUM Brazil*3 is equivalent to soccer ACCUM Brazil ACCUM Brazil ACCUM Brazil. Will score lower than Brazil is the largest nation in South Americaīut both documents will rank below soccer is the national sport of Brazil
Therefore, the document people play soccer because soccer is challenging and fun The term Brazil is weighted three times as heavily as soccer. For example, in a query of the form soccer, Brazil*3 You can assign different weights to different terms. The Oracle Text Scoring Algorithm for more information on how scores are calculated For example, enter the following combined ABOUT and word query: 'about(dogs) and cat'Ĭombine an ABOUT query with another ABOUT query as follows: 'about(dogs) not about(labradors)' Use other operators, such as AND or NOT, to combine ABOUT queries with word queries. You can also query on unstructured phrases, such as the following: 'about(japanese banking investments in indonesia)' In terms of scoring, documents which have all three themes will generally score higher than documents that have only one or two of the themes. In this English example, Oracle Text returns all documents that have themes of soccer, rules, or international competition. To search for documents that are about soccer, use the following syntax: 'about(soccer)'įurther refine the query to include documents about soccer rules in international competition by entering the phrase as the query term: 'about(soccer rules in international competition)' The fifth example shows that the AND operator has lower precedence than the WITHIN operator. The fourth example shows that the equivalence operator has higher precedence than the AND operator. In the third example, the fuzzy operator is first applied to w1, then the AND operator is applied to arguments w3 and w4, then the OR operator is applied to term w2 and the results of the AND operation, and finally, the score from the fuzzy operation on w1 is added to the score from the OR operation. In the second example, the query returns all documents that contain both w1 and w2 and all documents that contain w3. In the first example, because AND has a higher precedence than OR, the query returns all documents that contain w1 and all documents that contain both w2 and w3. Table 3-1 Query Expression Precedence Examples Query Expression
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