Updated doc.go for retrieving query id and connection id

Added an example to doc.go showing how to register callbacks in the query context to retrieve the connection and query Id.

Signed-off-by: Raymond Cypher <raymond.cypher@databricks.com>

Author: rcypher-databricks

doc.go

@@ -144,6 +144,36 @@ The result log may look like this:
 
 	{"level":"debug","connId":"01ed6545-5669-1ec7-8c7e-6d8a1ea0ab16","corrId":"workflow-example","queryId":"01ed6545-57cc-188a-bfc5-d9c0eaf8e189","time":1668558402,"message":"Run Main elapsed time: 1.298712292s"}
 
+# Programmatically Retrieving Connection and Query Id
+
+Use the driverctx package under driverctx/ctx.go to add callbacks to the query context to receive the connection id and query id.
+
+	import (
+		"github.com/databricks/databricks-sql-go/driverctx"
+	)
+
+	func main() {
+
+		...
+
+		qidCallback := func(id string) {
+			fmt.Println("query id: " + id)
+		}
+
+		connIdCallback := func(id string) {
+			fmt.Println("connection id: " + id)
+		}
+
+		ctx := context.Background()
+		ctx = driverctx.NewContextWithQueryIdCallback(ctx, qidCallback)
+		ctx = driverctx.NewContextWithConnIdCallback(ctx, connIdCallback)
+
+		rows, err1 := db.QueryContext(ctx, `select * from sometable`)
+
+		...
+
+	}
+
 # Errors
 
 There are three error types exposed via dbsql/errors