```
$ 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.
{
    if constexpr (is_decimal<T>)
    {
        readIntText<check_overflow>(x.value, buf);
    }
    else
    {
        readIntTextImpl<T, void, check_overflow>(x, buf);
    }
}
template <ReadIntTextCheckOverflow check_overflow = ReadIntTextCheckOverflow::CHECK_OVERFLOW, typename T>
bool tryReadIntText(T & x, ReadBuffer & buf)  
{
    return readIntTextImpl<T, bool, check_overflow>(x, buf);
}
/** More efficient variant (about 1.5 times on real dataset).
  * Differs in following:
  * - for numbers starting with zero, parsed only zero;
  * - symbol '+' before number is not supported;
  */
template <typename T, bool throw_on_error = true>
void readIntTextUnsafe(T & x, ReadBuffer & buf)