From 5669821b299427081f32de7d9d6712dff8b793dc Mon Sep 17 00:00:00 2001
From: moson-mo <mo-son@mailbox.org>
Date: Mon, 31 Oct 2022 18:00:39 +0100
Subject: [PATCH] perf: tweak some queries in mkpkglists

We can omit the "distinct" from some queries
because constraints in the DB ensure uniqueness:

* Groups sub-query
PackageGroup: Primary key makes "PackageID" + "GroupID" unique
Groups: Unique index on "Name" column
-> Technically we can't have a package with the same group-name twice

* Licenses sub-query:
PackageLicense -> Primary key makes "PackageID" + "LicenseID" unique
Licenses -> Unique index on "Name" column
-> Technically we can't have a package with the same license-name twice

* Keywords sub-query:
PackageKeywords -> Primary key makes "PackageBaseID" + "KeywordID" unique
(And a Package can only have one PackageBase)
Keywords -> Unique index on "Name" column
-> Technically we can't have a package with the same Keyword twice

* Packages main-query:
We join PackageBases and Users on their primary key columns
(which are guaranteed to be unique)
-> There is no way we could end up with more than one record for a Package

Signed-off-by: moson-mo <mo-son@mailbox.org>
---
 aurweb/scripts/mkpkglists.py | 10 +++-------
 1 file changed, 3 insertions(+), 7 deletions(-)

diff --git a/aurweb/scripts/mkpkglists.py b/aurweb/scripts/mkpkglists.py
index 7ff2690b..d2d11c5e 100755
--- a/aurweb/scripts/mkpkglists.py
+++ b/aurweb/scripts/mkpkglists.py
@@ -94,7 +94,7 @@ def get_extended_fields():
             models.PackageDependency.DepName.label("Name"),
             models.PackageDependency.DepCondition.label("Cond"),
         )
-        .distinct()
+        .distinct()  # A package could have the same dependency multiple times
         .order_by("Name"),
         # PackageRelation
         db.query(models.PackageRelation)
@@ -105,7 +105,7 @@ def get_extended_fields():
             models.PackageRelation.RelName.label("Name"),
             models.PackageRelation.RelCondition.label("Cond"),
         )
-        .distinct()
+        .distinct()  # A package could have the same relation multiple times
         .order_by("Name"),
         # Groups
         db.query(models.PackageGroup)
@@ -116,7 +116,6 @@ def get_extended_fields():
             models.Group.Name.label("Name"),
             literal(str()).label("Cond"),
         )
-        .distinct()
         .order_by("Name"),
         # Licenses
         db.query(models.PackageLicense)
@@ -127,7 +126,6 @@ def get_extended_fields():
             models.License.Name.label("Name"),
             literal(str()).label("Cond"),
         )
-        .distinct()
         .order_by("Name"),
         # Keywords
         db.query(models.PackageKeyword)
@@ -140,7 +138,6 @@ def get_extended_fields():
             models.PackageKeyword.Keyword.label("Name"),
             literal(str()).label("Cond"),
         )
-        .distinct()
         .order_by("Name"),
         # Co-Maintainer
         db.query(models.PackageComaintainer)
@@ -155,7 +152,7 @@ def get_extended_fields():
             models.User.Username.label("Name"),
             literal(str()).label("Cond"),
         )
-        .distinct()
+        .distinct()  # A package could have the same co-maintainer multiple times
         .order_by("Name"),
     ]
     query = subqueries[0].union_all(*subqueries[1:])
@@ -230,7 +227,6 @@ def _main():
             PackageBase.SubmittedTS.label("FirstSubmitted"),
             PackageBase.ModifiedTS.label("LastModified"),
         )
-        .distinct()
         .order_by("Name")
     )