database/sql: add support for multiple result sets
Many database systems allow returning multiple result sets
in a single query. This can be useful when dealing with many
intermediate results on the server and there is a need
to return more then one arity of data to the client.
Fixes #12382
Change-Id: I480a9ac6dadfc8743e0ba8b6d868ccf8442a9ca1
Reviewed-on: https://go-review.googlesource.com/30592
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
diff --git a/src/database/sql/sql_test.go b/src/database/sql/sql_test.go
index ca14af7..bce210d 100644
--- a/src/database/sql/sql_test.go
+++ b/src/database/sql/sql_test.go
@@ -319,6 +319,82 @@
}
}
+func TestMultiResultSetQuery(t *testing.T) {
+ db := newTestDB(t, "people")
+ defer closeDB(t, db)
+ prepares0 := numPrepares(t, db)
+ rows, err := db.Query("SELECT|people|age,name|;SELECT|people|name|")
+ if err != nil {
+ t.Fatalf("Query: %v", err)
+ }
+ type row1 struct {
+ age int
+ name string
+ }
+ type row2 struct {
+ name string
+ }
+ got1 := []row1{}
+ for rows.Next() {
+ var r row1
+ err = rows.Scan(&r.age, &r.name)
+ if err != nil {
+ t.Fatalf("Scan: %v", err)
+ }
+ got1 = append(got1, r)
+ }
+ err = rows.Err()
+ if err != nil {
+ t.Fatalf("Err: %v", err)
+ }
+ want1 := []row1{
+ {age: 1, name: "Alice"},
+ {age: 2, name: "Bob"},
+ {age: 3, name: "Chris"},
+ }
+ if !reflect.DeepEqual(got1, want1) {
+ t.Errorf("mismatch.\n got1: %#v\nwant: %#v", got1, want1)
+ }
+
+ if !rows.NextResultSet() {
+ t.Errorf("expected another result set")
+ }
+
+ got2 := []row2{}
+ for rows.Next() {
+ var r row2
+ err = rows.Scan(&r.name)
+ if err != nil {
+ t.Fatalf("Scan: %v", err)
+ }
+ got2 = append(got2, r)
+ }
+ err = rows.Err()
+ if err != nil {
+ t.Fatalf("Err: %v", err)
+ }
+ want2 := []row2{
+ {name: "Alice"},
+ {name: "Bob"},
+ {name: "Chris"},
+ }
+ if !reflect.DeepEqual(got2, want2) {
+ t.Errorf("mismatch.\n got: %#v\nwant: %#v", got2, want2)
+ }
+ if rows.NextResultSet() {
+ t.Errorf("expected no more result sets")
+ }
+
+ // And verify that the final rows.Next() call, which hit EOF,
+ // also closed the rows connection.
+ if n := db.numFreeConns(); n != 1 {
+ t.Fatalf("free conns after query hitting EOF = %d; want 1", n)
+ }
+ if prepares := numPrepares(t, db) - prepares0; prepares != 1 {
+ t.Errorf("executed %d Prepare statements; want 1", prepares)
+ }
+}
+
func TestByteOwnership(t *testing.T) {
db := newTestDB(t, "people")
defer closeDB(t, db)
