### Common Characteristics of SQL Injection Vulnerabilities

- During analysis, if it involves simple numeric concatenation, uses parameterized preprocessing and does not involve structural elements like column names or table names, or has other effective protections, the conclusion should be that no security vulnerability exists.
- During analysis, if it is a MongoDB NoSQL injection and structured queries are used (such as `bson.M`), and the taint parameter is strongly typed (not `interface{}`), preventing attackers from passing JSON objects or Maps to modify query logic, the conclusion should be that no security vulnerability exists.
- When the taint variable originates from a database, there may be a possibility of second-order injection.

### Notes

- Note that merely concatenating single quotes does not protect against SQL injection.
