```
$ echo '20210101,A' | clickhouse-local --input-format CSV --structure 'd Date, s String' --query "SELECT * FROM table"
Code: 27. DB::Exception: Cannot parse input: expected ',' before: '20210101,A\n': 
Row 1:
Column 0,   name: d, type: Date,   ERROR: text "20210101,A" is not like Date

: While executing ParallelParsingBlockInputFormat: While executing File. (CANNOT_PARSE_INPUT_ASSERTION_FAILED)
```

**How to solve**

Disambiguate while parsing by absense of separators between YYYY-MM-DD.
++buf.position();
        skipWhitespaceIfAny(buf);
        if (!buf.eof() && *buf.position() == ']') 
        {
            ++buf.position();
            return;
        }
        while (true)
        {
            skipJSONField(buf, name_of_field);
            skipWhitespaceIfAny(buf);
            if (!buf.eof() && *buf.position() == ',')
            {
                ++buf.position();
                skipWhitespaceIfAny(buf);
            }
            else if (!buf.eof() && *buf.position() == ']')
            {
                ++buf.position();
                break;
            }
            else
                throw Exception("Unexpected symbol for key '" + name_of_field.toString() + "'", ErrorCodes::INCORRECT_DATA);
        }
    }
    else if (*buf.position() == '{') 
    {
        ++buf.position();
        skipWhitespaceIfAny(buf);
        while (!buf.eof() && *buf.position() != '}')