Displays information about columns in the specified table that are required to uniquely identify records in a table. The result may consist of one or more columns. In normal situations, this would be the primary key field.
The type parameter has a value of 0 or 1, indicating whether the columns returned identify unique rows or identify columns that are updated when any value in the row is updated. nullable has a value of 0 or 1, indicating that the columns accept null values or are not nullable, respectively.
The result set contains the columns SCOPE, COLUMN_NAME, DATA_TYPE, TYPE_NAME, COLUMN_SIZE, BUFFER_LENGTH, DECIMAL_DIGITS, and PSEUDO_COLUMN, with the results ordered by SCOPE.
PHP Functions Essential Reference. Copyright © 2002 by New Riders Publishing (Authors: Zak Greant, Graeme Merrall, Torben Wilson, Brett Michlitsch). This material may be distributed only subject to the terms and conditions set forth in the Open Publication License, v1.0 or later (the latest version is presently available at http://www.opencontent.org/openpub/). The authors of this book have elected not to choose any options under the OPL. This online book was obtained from http://www.fooassociates.com/phpfer/ and is designed to provide information about the PHP programming language, focusing on PHP version 4.0.4 for the most part. The information is provided on an as-is basis, and no warranty or fitness is implied. All persons and entities shall have neither liability nor responsibility to any person or entity with respect to any loss or damage arising from the information contained in this book.