fix(otelgorm): renamed var and added readme

otelgorm/README.md

@@ -44,6 +44,14 @@ if err := db.WithContext(ctx).Raw("SELECT 42").Scan(&num).Error; err != nil {
 
 See [example](/example/) for details.
 
+## Usage: exceptions
+
+In case you want to omit certain database operations from any trace/span, you can also set:
+```go
+db.Set(EnabledTraceDatabaseKey, false)
+```
+This will omit the database queries following after from any trace.
+
 ## Options
 
 You can customize the plugin using configuration

otelgorm/option.go

@@ -7,7 +7,7 @@ import (
 )
 
 const (
-	DisabledTraceDatabaseKey = "otelgorm-trace-enabled"
+	EnabledTraceDatabaseKey = "otelgorm-trace-enabled"
 )
 
 type Option func(p *otelPlugin)

otelgorm/otelgorm.go

@@ -101,7 +101,7 @@ type parentCtxKey struct{}
 // checkTraceEnabled checks if the 'special' database key was set and if so returns it
 // This allows you to disable starting/registering a new trace for certain operations
 func checkTraceEnabled(db *gorm.DB) bool {
-	value, ok := db.Get(DisabledTraceDatabaseKey)
+	value, ok := db.Get(EnabledTraceDatabaseKey)
 
 	// If value is not specifically set, it should start a new trace
 	if !ok {