# sql: Scan error on column index 2: converting NULL to string is unsupported

- **ID:** `go/sql-nil-value-scan`
- **Domain:** go
- **Category:** data_error
- **Verification:** ai_generated
- **Fix Rate:** 80%

## Root Cause

数据库字段为NULL，但Scan目标类型不支持NULL

## Version Compatibility

| Version | Status | Introduced | Deprecated |
|---------|--------|------------|------------|
| 1.13 | active | — | — |

## Workarounds

1. **** (95% success)
   ```
   使用sql.NullString类型
   ```
2. **** (85% success)
   ```
   在SQL查询中使用COALESCE
   ```

## Dead Ends

- **** — NULL仍然无法转换为string (90% fail)
- **** — 数据丢失 (60% fail)