602SQL Documentation Index  

Storing Documents in a Fulltext System

Documents stored in the fulltext system consist of:

You can use the FTX_DOCIDid sequence to generate unique numbers for new documents. Usually, the column with the document number will have the defined default value of FTX_DOCIDid.nextval. This default value will ensure that each new record in the document table will receive a unique document number automatically.

You can index documents from multiple document tables in a single fulltext system. However, in this case, it is required to ensure that document numbers are unique for all tables. A single sequence should be used to generate numbers for this group of tables. Document numbers MUST be positive.

You can index more columns from a document table in a fulltext system. You can choose from the following methods:

You can create a table to store the documents in the following way:

CREATE TABLE Txtab (doc_number INTEGER DEFAULT ftx_docidCorrespondence.nextval, tx LONG VARCHAR, PRIMARY KEY (doc_number))

Words in a Document

A word (for indexing and document search) is considered an order of characters beginning with a letter, number, the @ or _ symbol, and dashes (e.g. MS-DOS is a single word, but TCP/IP is two words. ABC_DE_@14-23X is a word, but /123X is not).

The set of characters allowed in a word and the set of characters allowed in a beginning of a word can be optionally set (clauses WORD_STARTERS a WORD_CHARS in CREATE FULLTEXT) statement.

Words are not case sensitive for indexing and document search. However, you can search words using a specific case.

There are certain groups of words in each language (contractions, prepositions, etc.) that are not indexed.