Error while extract schema

[dofy1034]

Hello,

I found if using a function that contains keywords, like fromUnixTimestamp64Milli, I got an error result when extract db and table name.

Here is code snippet:

private String extractDBAndTableName(String sql) {
        if (Utils.startsWithIgnoreCase(sql, "select")) {
            String withoutStrings = Utils.retainUnquoted(sql, '\'');
            int fromIndex = withoutStrings.indexOf("from");
            if (fromIndex == -1) {
                fromIndex = withoutStrings.indexOf("FROM");
            }
            if (fromIndex != -1) {
                String fromFrom = withoutStrings.substring(fromIndex);
                String fromTable = fromFrom.substring("from".length()).trim();
                return fromTable.split(" ")[0];
            }
        }
        if (Utils.startsWithIgnoreCase(sql, "desc")) {
            return "system.columns";
        }
        if (Utils.startsWithIgnoreCase(sql, "show")) {
            return "system.tables";
        }
        return "system.unknown";
    }