Convert nvarchar(max) to varbinary(max)

Question

Have table with values ``` report nvarchar(max) not null description nvarchar(max) ``` In stored procedure I want select values from table and then convert it to varbinary max. I seletct : ``` select CONVERT(varbinary(max), [report]) as [report], ISNULL(CONVERT(varbinary(max), [description]), '') as [description] from myTbl ``` but I get an error: Implicit conversion from data type varchar to varbinary(max) is not allowed. Use the CONVERT function to run this query. Please help me to solve this problem

Accepted Answer

The failure is occurring because you convert description to `varbinary`, but then try to cast any null values back to a `varchar`. You just need to move `ISNULL` inside the `CONVERT` or change the conversion value when null to a binary value.

ISNULL in CONVERT

```
SELECT 
    CONVERT(varbinary(MAX), report), 
    CONVERT(varbinary(max), ISNULL([description], '')) as [description]
FROM myTbl
```

Proper ISNULL Value

```
SELECT 
    CONVERT(varbinary(MAX), report), 
    ISNULL(CONVERT(varbinary(max), [description]), 0x) as [description]
FROM myTbl
```

Both versions will produce the same output `0x` if description is null.

Convert nvarchar(max) to varbinary(max)

Solution

Problem