Comment Operators

Compared to the original MogDB, dolphin's changes to the comment operators are mainly:

1. Support has been added for indicating the start of a single line comment via #. For example, # select a from t1 indicates a single comment.

• Single line comment at the beginning of #

  Description: Treats comments starting with # and ending with a newline as comments.

  Note: This operator is intended for use with B-compatible databases and has different semantics than MogDB's original # operator. To use this semantics, create a B-compatible database, enable the MySQL Compatibility SQL Engine plugin, and set dolphin.b_compatibility_mode to TRUE.

  Example:

  MogDB=# SELECT lower('TOM') #1234;
  MogDB=# ;
  lower
  -------
  tom