Add latest changes from gitlab-org/gitlab@master

1 files changed, 7 insertions, 0 deletions

diff --git a/doc/development/pipelines/index.md b/doc/development/pipelines/index.md
index 51cdd12a8c1..b56259dbdaf 100644
--- a/doc/development/pipelines/index.md
+++ b/doc/development/pipelines/index.md
@@ -541,6 +541,13 @@ By default, all tests run with [multiple databases](../database/multiple_databas
 
 We also run tests with a single database in nightly scheduled pipelines, and in merge requests that touch database-related files.
 
+Single database tests run in two modes:
+
+1. **Single database with one connection**. Where GitLab connects to all the tables using one connection pool.
+This runs through all the jobs that end with `-single-db`
+1. **Single database with two connections**. Where GitLab connects to `gitlab_main`, `gitlab_ci` database tables
+using different database connections. This runs through all the jobs that end with `-single-db-ci-connection`.
+
 If you want to force tests to run with a single database, you can add the `pipeline:run-single-db` label to the merge request.
 
 ## Monitoring