Describe the bug
When I want to get the currently used database, I find that it cannot be parsed

To Reproduce
Steps to reproduce the behavior:

1. Example SQL
   String sql = "select database()";
2. Parsing this SQL using JSqlParser with this statements
   CCJSqlParserUtil.parse(sql);
3. Exception

Encountered unexpected token: "database" "DATABASE"
    at line 1, column 8.

Was expecting one of:

    "*"
    "STRAIGHT_JOIN"

Expected behavior

System

• mysql 8.0.27
• jdk-liberica-11.0.13
• 4.2 or 4.3