ANSI/INCITS 500-2012
This standard specifies SQL language syntax and semantics that permit applications to identify row pattern matches by using extended regular expressions applied to rows of base and derived tables. A key component of this standard is the use of row pattern variables that span subsequences of rows, defined using conditions on individual rows and on aggregates of rows. The primary syntax element defined in this standard is the MATCH_RECOGNIZE clause, which is applied to table expressions.