Consultor Eletrônico

Status: Unverified

GOAL:

Using word indexes for status indicator

FIX:

A word index is a special index type that you can define for a character field, that indexes not the entire field value, as a normal index would, but every individual word in the index. There are delimiters you can define to tell the database manager just what you would like to see treated as a ·word·, what the delimiters between words are, and so forth.

Word indexes can be a tremendously powerful mechanism for identifying database fields that contain particular words. In fact, there is a special CONTAINS operator for a WHERE clause, similar to BEGINS and MATCHES, which is reserved for use with word indexes.

One powerful use of word indexes is not just to provide an index on all the words in a free text field such as a status message or customer comments, but to create special character fields in which you store strings that identify other aspects of the record. For example, you can create a character field for a table in which you store various attributes of the record that otherwise would be individual logical fields with True/False values. It·s much more efficient to use the CONTAINS operator on a word-indexed field than to evaluate a number of different indexed fields. You can also store some combination of field names and field values in a word indexed field to make it easier and faster to find a record based on a number of different search criteria, such as customers where you have some particular bits and pieces of name and address information.