anchor.diff:  
   * `_pattern_`
   +
  -is a character value expression that specifies the pattern string for
  -the search in form of Regular Expression.
  -The Trafodion Regular Expression is following the POSIX regular expression rules.
  +is a character value expression that specifies a regular expression. 
  +Trafodion regular expressions follow POSIX regular expression rules.
   
   
   [[using_not]]
  
positive.code: [[regexp_syntax]]
  ==== Syntax
  ```
  match-value [NOT] REGEXP pattern
  ```
  
  * `_match-value_`
  
negative.code: | <<in_predicate,IN Predicate>> | Determines if a sequence of values is equal to any of the sequences of
  values in a list of sequences.
  | <<like_predicate,LIKE Predicate>> | Searches for character strings that match a pattern.
  | <<regexp_predicate,REGEXP Predicate>> | Searches for character strings that match an extended regular expression.
  | <<null_predicate,NULL Predicate>> | Determines whether all the values in a sequence of values are null.
  | <<quantified_comparison_predicates,Quantified Comparison Predicates>> +  
  (ALL, ANY, SOME ) | Compares the values of sequences of expressions to the values in each
  