```
$ 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.
#endif
                while (next_pos < buf.buffer().end()
                    && *next_pos != delimiter && *next_pos != '\r' && *next_pos != '\n')
                    ++next_pos;
            }();
            appendToStringOrVector(s, buf, next_pos);
            buf.position() = next_pos;
            if (!buf.hasPendingData())
                continue;
            /** CSV format can contain insignificant spaces and tabs.
              * Usually the task of skipping them is for the calling code.
              * But in this case, it will be difficult to do this, so remove the trailing whitespace by ourself.
              */
            size_t size = s.size();
            while (size > 0
                && (s[size - 1] == ' ' || s[size - 1] == '\t'))
                --size;
            s.resize(size);
            return;
        }
    }
}
void readCSVString(String & s, ReadBuffer & buf, const FormatSettings::CSV & settings)
{
    s.clear();
    readCSVStringInto(s, buf, settings);
}
template void readCSVStringInto<PaddedPODArray<UInt8>>(PaddedPODArray<UInt8> & s, ReadBuffer & buf, const FormatSettings::CSV & settings);
template <typename Vector, typename ReturnType>
ReturnType readJSONStringInto(Vector & s, ReadBuffer & buf)