Oracle Database 12c PL/SQL Programming

APPENDIX

E

Regular Expression Primer

Regular expressions in Oracle Database 12c haven’t changed from Oracle Database 11g. They enable you to perform powerful context searches in variable-length strings, like the CHAR, CLOB, NCHAR, NCLOB, NVARCHAR2, and VARCHAR2 character data types. Regular expressions are strings that describe or match a set of strings. They provide a powerful set of pattern matching capabilities by combining character classes, collation classes, metacharacters, metasequences, and literals. Character classes are groups of possible characters at a point in the search. Collation classes are sets of characters and are treated like ...