Partition the package_derivations_by_guix_revision_range table

And create a proper git_branches table in the process.

I'm hoping this will help with slow deletions from the
package_derivations_by_guix_revision_range table in the case where there are
lots of branches, since it'll separate the data for one branch from another.

These migrations will remove the existing data, so
rebuild-package-derivations-table will currently need manually running to
regenerate it.

guix-data-service/model/git-branch.scm

@@ -21,32 +21,52 @@
   #:use-module (squee)
   #:use-module (srfi srfi-19)
   #:use-module (guix-data-service model utils)
-  #:export (insert-git-branch-entry
+  #:export (git-branch-for-repository-and-name
+            insert-git-branch-entry
             git-branches-for-commit
             git-branches-with-repository-details-for-commit
             most-recent-commits-for-branch
             latest-processed-commit-for-branch
             all-branches-with-most-recent-commit))
 
+(define (git-branch-for-repository-and-name conn
+                                            git-repository-id
+                                            name)
+  (match (exec-query
+          conn
+          "
+SELECT id
+FROM git_branches
+WHERE git_repository_id = $1
+  AND name = $2"
+          (list (number->string git-repository-id)
+                name))
+    (#f #f)
+    (((id)) (string->number id))))
+
 (define (insert-git-branch-entry conn
-                                 name commit
-                                 git-repository-id datetime)
-  (exec-query
-   conn
-   (string-append
-    "INSERT INTO git_branches (name, commit, git_repository_id, datetime) "
-    "VALUES ($1, $2, $3, to_timestamp($4)) "
-    "ON CONFLICT DO NOTHING")
-   (list name
-         commit
-         (number->string git-repository-id)
-         (date->string datetime "~s"))))
+                                 git-repository-id
+                                 name)
+  (match (exec-query
+          conn
+          "
+INSERT INTO git_branches (git_repository_id, name)
+VALUES ($1, $2)
+RETURNING id"
+          (list (number->string git-repository-id)
+                name))
+    (((id))
+     (string->number id))))
 
 (define (git-branches-for-commit conn commit)
   (define query
     "
-SELECT name, datetime FROM git_branches WHERE commit = $1
-ORDER BY datetime DESC")
+SELECT name, git_commits.datetime
+FROM git_commits
+INNER JOIN git_branches
+  ON git_commits.git_branch_id = git_branches.id
+WHERE commit = $1
+ORDER BY git_commits.datetime DESC")
 
   (exec-query conn query (list commit)))
 
@@ -55,16 +75,49 @@ ORDER BY datetime DESC")
     "
 SELECT git_repositories.id, git_repositories.label,
        git_repositories.url, git_repositories.cgit_url_base,
-       git_branches.name, git_branches.datetime
-FROM git_branches
+       git_branches.name, git_commits.datetime
+FROM git_commits
+INNER JOIN git_branches
+  ON git_commits.git_branch_id = git_branches.id
 INNER JOIN git_repositories
   ON git_branches.git_repository_id = git_repositories.id
-WHERE git_branches.commit = $1")
+WHERE git_commits.commit = $1")
 
   (group-list-by-first-n-fields
    4
    (exec-query conn query (list commit))))
 
+(define* (latest-processed-commit-for-branch conn repository-id branch-name)
+  (define query
+    (string-append
+     "
+SELECT git_commits.commit
+FROM git_branches
+INNER JOIN git_commits
+  ON git_branches.id = git_commits.git_branch_id
+INNER JOIN guix_revisions
+  ON git_commits.commit = guix_revisions.commit
+INNER JOIN load_new_guix_revision_jobs
+  ON load_new_guix_revision_jobs.commit = guix_revisions.commit
+INNER JOIN load_new_guix_revision_job_events
+  ON job_id = load_new_guix_revision_jobs.id
+WHERE guix_revisions.git_repository_id = $1
+  AND git_branches.git_repository_id = $1
+  AND git_branches.name = $2
+  AND load_new_guix_revision_job_events.event = 'success'
+ORDER BY datetime DESC
+LIMIT 1"))
+
+  (match (exec-query
+          conn
+          query
+          (list repository-id branch-name))
+    (((commit-hash))
+     commit-hash)
+    ('()
+     #f)))
+
+
 (define* (most-recent-commits-for-branch conn git-repository-id
                                          branch-name
                                          #:key
@@ -74,7 +127,7 @@ WHERE git_branches.commit = $1")
   (define query
     (string-append
      "
-SELECT git_branches.commit,
+SELECT git_commits.commit,
        datetime,
        (
          load_new_guix_revision_job_events.event IS NOT NULL
@@ -84,12 +137,14 @@ SELECT git_branches.commit,
           FROM load_new_guix_revision_job_events
           INNER JOIN load_new_guix_revision_jobs ON
             load_new_guix_revision_jobs.id = load_new_guix_revision_job_events.job_id
-          WHERE load_new_guix_revision_jobs.commit = git_branches.commit AND
+          WHERE load_new_guix_revision_jobs.commit = git_commits.commit AND
                 git_branches.git_repository_id = load_new_guix_revision_jobs.git_repository_id
        ) AS job_events
 FROM git_branches
+INNER JOIN git_commits
+  ON git_branches.id = git_commits.git_branch_id
 LEFT OUTER JOIN guix_revisions
-  ON git_branches.commit = guix_revisions.commit
+  ON git_commits.commit = guix_revisions.commit
 LEFT JOIN load_new_guix_revision_jobs
   ON load_new_guix_revision_jobs.commit = guix_revisions.commit
 LEFT JOIN load_new_guix_revision_job_events
@@ -129,40 +184,12 @@ LIMIT " (number->string limit))
     (list branch-name
           (number->string git-repository-id)))))
 
-(define* (latest-processed-commit-for-branch conn repository-id branch-name)
-  (define query
-    (string-append
-     "
-SELECT git_branches.commit
-FROM git_branches
-INNER JOIN guix_revisions
-  ON git_branches.commit = guix_revisions.commit
-INNER JOIN load_new_guix_revision_jobs
-  ON load_new_guix_revision_jobs.commit = guix_revisions.commit
-INNER JOIN load_new_guix_revision_job_events
-  ON job_id = load_new_guix_revision_jobs.id
-WHERE guix_revisions.git_repository_id = $1
-  AND git_branches.git_repository_id = $1
-  AND git_branches.name = $2
-  AND load_new_guix_revision_job_events.event = 'success'
-ORDER BY datetime DESC
-LIMIT 1"))
-
-  (match (exec-query
-          conn
-          query
-          (list repository-id branch-name))
-    (((commit-hash))
-     commit-hash)
-    ('()
-     #f)))
-
 (define (all-branches-with-most-recent-commit conn git-repository-id)
   (define query
     (string-append
      "
 SELECT DISTINCT ON (name)
-  name, git_branches.commit,
+  name, git_commits.commit,
   datetime,
   (
     load_new_guix_revision_jobs.succeeded_at IS NOT NULL
@@ -172,14 +199,16 @@ SELECT DISTINCT ON (name)
     FROM load_new_guix_revision_job_events
     INNER JOIN load_new_guix_revision_jobs ON
       load_new_guix_revision_jobs.id = load_new_guix_revision_job_events.job_id
-    WHERE load_new_guix_revision_jobs.commit = git_branches.commit AND
+    WHERE load_new_guix_revision_jobs.commit = git_commits.commit AND
           git_branches.git_repository_id = load_new_guix_revision_jobs.git_repository_id
   ) AS job_events
 FROM git_branches
+INNER JOIN git_commits
+  ON git_branches.id = git_commits.git_branch_id
 LEFT OUTER JOIN guix_revisions
-  ON git_branches.commit = guix_revisions.commit
+  ON git_commits.commit = guix_revisions.commit
 LEFT JOIN load_new_guix_revision_jobs
-  ON git_branches.commit = load_new_guix_revision_jobs.commit
+  ON git_commits.commit = load_new_guix_revision_jobs.commit
  AND git_branches.git_repository_id = load_new_guix_revision_jobs.git_repository_id
 WHERE git_branches.git_repository_id = $1
 ORDER BY name, datetime DESC"))
@@ -199,4 +228,3 @@ ORDER BY name, datetime DESC"))
     conn
     query
     (list (number->string git-repository-id)))))
-