[BUG] JSQLParser Version :4.7 : Failing to parse informix isolation level statement

[shubhjet]

I am using Informix and jsql parser to parse the SQL statements.

Failing SQL Feature:

• While using jsql parser with Informix if we use Informix set isolation statement then i got an Error in parsing error
• Example: set isolation to dirty read; can't be parsed

SQL Example:

```set isolation to dirty read;```

Software Information:

• JSqlParser version
• Database (e. g. IBM Informix )

Tips:

I have a string of multiple SQL statements and using CCJSqlParserUtil.parseStatements(sql); to parse the statements, but in case of above statement I am getting parsing error.

net.sf.jsqlparser.parser.ParseException: Encountered unexpected token: "DIRTY" <S_IDENTIFIER> Was expecting one of:

","
"."
"::"
"["
"^" 
<EOF>
<ST_SEMICOLON>