Re: Index Creation Questions

Schultheis, Carol L wrote: > > Can someone answer some basic general questions? > > 1. what is the difference between creating a unique index on a column > via the create unique index statement > versus using the primary key constraint when creating the table. The second one creates a unique index AND allows you to use referential integrity. > 2. what is the difference between creating an index on a column via the > create index statement > versus using the alter table and adding a foreign key constraint. The second one creates an index AND implements automatic referential integrity. > 3. what does the dbexport/dbimport facility do when indices are created > by using constraints versus > the create index statement, specifically when the dbimport creates > the table, is the data then loaded > before the constraints create the index??????? All constraints are created using ALTER TABLE statements AFTER the data is loaded into the table. Hope that helps, -- Mark. +----------------------------------------------------------+-----------+ |Mark D. Stock - Informix SA http://www.informix.com |//////// /| |mailto:mdstock@informix.com http://www.informix.com/idn |///// / //| |http://www.iiug.org +-----------------------------------+//// / ///| | Tel: +27 11 807 0313 |If it's slow, the users complain. |/// / ////| | Fax: +27 11 807 2594 |If it's fast, the users keep quiet.|// / /////| |Cell: +27 83 250 2325 |Therefore, "No news: travels fast"!|/ ////////| +----------------------+-----------------------------------+-----------+