```
$ 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.
template <is_integer T>
inline void readTextWithSizeSuffix(T & x, ReadBuffer & buf)
{
    readIntText(x, buf);
    if (buf.eof())
        return;
    
    auto finish = [&buf, &x] (UInt64 base, int power_of_two) mutable
    {
        ++buf.position();
        if (buf.eof())
        {
            x *= base; 
        }
        else if (*buf.position() == 'i')
        {
            x = (x << power_of_two); 
            ++buf.position();
        }
        return;
    };
    switch (*buf.position())
    {
        case 'k': [[fallthrough]];
        case 'K':
            finish(1000, 10);
            break;