如何在Golang中动态映射数据库表？

I have to create a JSON from a MS-SQL Database through Go. The problem is that some database fields are created dynamically in backend system (not Go).

There could be:

type Demotable struct{
Id int
Name string
Adress int
Z_somedynamicfield string
Z_anotherfield int
}

All fields prefixed with "Z_" are dynamic, so struct could also be:

type Demotable struct{
Id int
Name string
Adress int
Z_completedifferent int
Z_notlikefirst string
Z_evenmorefields string
}

I also have a helper table where every "dynamic field" is described:

| tableName | fieldName          | fieldType |
+-----------+--------------------+-----------+
| Demotable | Z_somedynamicfield | string    |
+-----------+--------------------+-----------+
| Demotable | Z_anotherfield     | int       |
...

Ideally I would dynamically "extend" struct with infos from helper table - but I don't have an idea how or if this even is possible?

I would sugges first querying the current tables of your table through a prepared statement:

SELECT * FROM [DatabaseName].INFORMATION_SCHEMA.COLUMNS
WHERE TABLE_NAME = N'MyTable'

Store the results of the query in a string slice. After doing so, create a map with string keys and *interface{} values.

 results := make(map[string](*interface{})

While iterating over results of your actual query, you can finally assign the values from your previous query to map the results.

Kyle Banks offers a great explanation on receiving dynamic results from Query results on this article.

If for any reason you need to actually specify the type of the results, the reflect package will be of a lot of help on auto-resolving the value type for your needs.