# sql: Scan error on column index 2, name "email": converting NULL to string is unsupported

- **ID:** `go/sql-converting-null-to-string`
- **Domain:** go
- **Category:** data_error
- **Verification:** ai_generated
- **Fix Rate:** 80%

## Root Cause

A nullable column was scanned into a non-pointer string. NULL cannot be assigned to string.

## Version Compatibility

| Version | Status | Introduced | Deprecated |
|---------|--------|------------|------------|
| 1.18 | active | — | — |
| 1.21 | active | — | — |

## Workarounds

1. **** (92% success)
   ```
   var email sql.NullString
err := row.Scan(&email)
if email.Valid { u.Email = email.String }
   ```
2. **** (88% success)
   ```
   Use a pointer *string for nullable columns.
   ```

## Dead Ends

- **** — Loses the distinction between empty and NULL. (60% fail)
- **** — Requires type assertion and is error-prone. (65% fail)