问题： 文档(https://ci.apache.org/projects/flink/flink-docs-release-1.10/dev/table/sql/queries.html#scan-projection-and-filter)使用'%'求余运算，在SQL解析报错: org.apache.calcite.sql.parser.SqlParseException: Percent remainder '%' is not allowed under the current SQL conformance level
MYSQL conformance 支持'%'运算，使用MYSQL CONFORMANCE，在SQL语法校验过程会找不到'%'对应的SqlOperator
