Fix Count: honor custom SELECT count expressions, avoid extra columns

[StounhandJ]

• Do only one thing
• Non breaking API changes
• Tested

What did this pull request do?

When creating a Count request, if a Select was passed with count, substitute it in Clause to avoid unexpected addition of the request.

User Case Description

InnerJoins is used here as adding an internal verification condition.

r.db.Model(&models.KubeRBAC{}).
	Select("count(distinct(subj->>'kind', subj->>'apiGroup', subj->>'name', subj->>'namespace', \"ClusterRef\".id))").
	InnerJoins("ClusterRef").
	Count(&total)

Extra fields appear in the final sql, which violates the correctness of the work.

SELECT
  count(distinct(
    subj->>'kind',
    subj->>'apiGroup',
    subj->>'name',
    subj->>'namespace',
    "ClusterRef".id
  )),
  "ClusterRef"."id"         AS "ClusterRef__id",
  "ClusterRef"."name"       AS "ClusterRef__name",
  "ClusterRef"."updated_at" AS "ClusterRef__updated_at",
  "ClusterRef"."created_at" AS "ClusterRef__created_at"
FROM
  "kube_rbac"
INNER JOIN
  "kube_clusters" "ClusterRef"
    ON "kube_rbac"."kube_cluster_id" = "ClusterRef"."id"
    AND "ClusterRef"."updated_at" > now() - '1 hours'::interval;

The result after correction

SELECT
  count(distinct(
    subj->>'kind',
    subj->>'apiGroup',
    subj->>'name',
    subj->>'namespace',
    "ClusterRef".id
  ))
FROM
  "kube_rbac"
INNER JOIN
  "kube_clusters" "ClusterRef"
    ON "kube_rbac"."kube_cluster_id" = "ClusterRef"."id"
    AND "ClusterRef"."updated_at" > now() - '1 hours'::interval;

[propel-code-bot]

Fix: prevent duplicate select columns when Count() receives an explicit COUNT expression

The PR adjusts the Count() implementation so that when the caller has already supplied an explicit COUNT(...) expression via Select(), GORM will reuse that expression as the SELECT clause instead of auto-appending its own COUNT(*). This eliminates unintended extra columns in generated SQL, especially when JOINs are present. A corresponding regression test covering DISTINCT with JOIN has been added.

Key Changes

• Added prefix check for count( in finisher_api.go and inject clause.Select with the provided expression instead of defaulting to COUNT(*)
• Extended tests/count_test.go with two dry-run cases validating Distinct + Join path

Affected Areas

• finisher_api.go – logic inside Count() around clause.Select handling
• tests/count_test.go – new test cases

This summary was automatically generated by @propel-code-bot

[jinzhu]

Hi @StounhandJ

Can you add some tests?

[StounhandJ]

Hi @jinzhu

I missed the message, but here are two Count tests along with the Join

[StounhandJ]

Hi @jinzhu

This change is necessary to remove the existing workarounds. Without it, we are forced to keep temporary patches in place, which is not sustainable in the long term.