launchpad-reviewers team mailing list archive

[Jürgen Gmach <mp+416670@xxxxxxxxxxxxxxxxxx>]

Jürgen Gmach has proposed merging ~jugmac00/launchpad:create-preserving-query-count-how-to into launchpad:master.

Commit message:
Create `Preserving query count` how-to

Requested reviews:
  Launchpad code reviewers (launchpad-reviewers)

For more details, see:
https://code.launchpad.net/~jugmac00/launchpad/+git/launchpad/+merge/416670
-- 
Your team Launchpad code reviewers is requested to review the proposed merge of ~jugmac00/launchpad:create-preserving-query-count-how-to into launchpad:master.

diff --git a/doc/how-to/preserve-query-count.rst b/doc/how-to/preserve-query-count.rst
new file mode 100644
index 0000000..c36197f
--- /dev/null
+++ b/doc/how-to/preserve-query-count.rst
@@ -0,0 +1,19 @@
+======================
+Preserving query count
+======================
+
+Given you want to read or create many items instead of one,
+you need to make sure that the number of queries stays constant.
+
+In Launchpad this can be done by using the `StormStatementRecorder`,
+as outlined in the following example:
+
+.. code-block:: python
+
+    def test_newNamedAuthTokens_query_count(self):
+        ...
+        with StormStatementRecorder() as recorder1:
+            self.private_ppa.newNamedAuthTokens("tok1")
+        with StormStatementRecorder() as recorder2:
+            self.private_ppa.newNamedAuthTokens(("tok1", "tok2", "tok3"))
+        self.assertThat(recorder2, HasQueryCount.byEquality(recorder1))
diff --git a/doc/index.rst b/doc/index.rst
index f967be6..d3407ce 100644
--- a/doc/index.rst
+++ b/doc/index.rst
@@ -35,6 +35,7 @@ How-to Guides
    how-to/avoid-debugging-issues
    how-to/apply-schema-changes
    how-to/use-updated-dependency
+   how-to/preserve-query-count
 
 Explanation
 ===========