T581, Regular expression substring function


The specification states the following:

 Subclause 6.30, "<string value function>":
 <regular expression substring function> ::=
 SUBSTRING <left paren> <character value expression> SIMILAR <character value expression>
 ESCAPE <escape character> <right paren>
 Conformance Rules
 Without Feature T581, "Regular expression substring function", conforming SQL language shall not contain a <regular expression substring function>.

Microsoft SQL Server 2008 R2 and Microsoft SQL Server 2012 vary as follows:

Transact-SQL does not support this feature.