CSA Preface 

Standards development within the Information Technology sector is harmonized with international standards development. Through the CSA Technical Committee on Information Technology (TCIT), Canadians serve as the SCC Mirror Committee (SMC) on ISO/IEC Joint Technical Committee 1 on Information Technology (ISO/IEC JTC1) for the Standards Council of Canada (SCC), the ISO member body for Canada and sponsor of the Canadian National Committee of the IEC. For brevity, this Standard will be referred to as "CSA ISO/IEC 19075-1" throughout. The International Standard was reviewed by the CSA TCIT under the jurisdiction of the CSA Strategic Steering Committee on Information and Communications Technology and deemed acceptable for use in Canada. This Standard has been formally approved, without modification, by the Technical Committee and has been developed in compliance with Standards Council of Canada requirements for National Standards of Canada. It has been published as a National Standard of Canada by CSA Group. 

Scope 

This document describes the regular expression support in SQL (ISO/IEC 9075-2) adopted from the regular expression syntax of XQuery and XPath Functions and Operators 3.1, which is derived from Perl. This document discusses five operators using this regular expression syntax:

- LIKE_REGEX predicate, to determine the existence of a match to a regular expression. 

- OCCURRENCES_REGEX numeric function, to determine the number of matches to a regular expression. 

- POSITION_REGEX function, to determine the position of a match. 

- SUBSTRING_REGEX function, to extract a substring matching a regular expression. 

- TRANSLATE_REGEX function, to perform replacements using a regular expression.