Working With Indexes

Index
TurboDB Components
    TTdbDataSet
    TTdbTable
    TTdbBatchMove
Turbo Database
    Overview
    Colum Data Types
    Queries
    Operators and Functions
    Working with Indexes
    Automatic Linking
    Working with Link and Relation Fields
    Shared Tables
    Table Locks
    Data Security
TurboDB Tools
    TurboDB Workbench
    TurboDB Data Exchange
    dataWeb Builder
    Visua Data Publisher
OperatorsAndFunctions.html Frequently Asked Questions

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Indexes are additional files for a database table that enable fast searching and sorting. TurboDB indexes are built on either a list of field names or an expression to define the sorting order. If an index is declared to be unique, records that would create a duplicate key in the index are not accepted. Another form of indexes are full-text indexes.

Indexes Based on a Field List

These indexes are sorted in the order of the first field in the field list. If two records have the same value for the first field they are sorted after the second field of the field list and so on. There can be up to 10 fields in the index field list. Every field can be sorted in ascending or in descending order.

Indexes Based on an Expression

These indexes are sorted after the value of an arbitrary expression that can be up to 40 characters long. If the expression is of string type, the index is sorted like if the expression values were values of a string column. If the expression is of numeric type, the index is sorted according to normal numeric order.

Full-Text Indexes

A full-text index enables the user to search for a keyword or a set of keywords in any field of the table. Full-text indexes in TurboDB are not real database indexes but additional database tables that are linked in a many-to-many relation to the base table.

Indexes can be created and deleted with various TurboDB tools at design time. At run time use TTdbTable.AddIndex and TTdbTable.DeleteIndex.

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Last updated on 11/19/2000. Copyright (c) 2000 by dataWeb GmbH, Aicha, Germany. Turbo Database and TurboDB Components are products by dataWeb - the manufacturers of RAD tools for the Web. Please send your hints, questions and comments to Peter Pohmann.