BS ISO/IEC 19075-1:2021 - Page 2

Information technology. Guidance for the use of database language SQL. XQuery regular expressions | Status: Current, Project Underway

1 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.