Add todos config for multiple partition scan detector

Relates to https://gitlab.com/gitlab-org/gitlab/-/issues/428704

scripts/database/query_analyzers.rb

 # frozen_string_literal: true
 
+require 'yaml'
+
 class Database
   class QueryAnalyzers
     attr_reader :analyzers
 
     def initialize
-      @analyzers = ObjectSpace.each_object(::Class).select { |c| c < Base }.map(&:new)
+      config = YAML.safe_load_file(File.expand_path('query_analyzers.yml', __dir__))
+      @analyzers = self.class.all.map do |subclass|
+        subclass_name = subclass.to_s.split('::').last
+        subclass.new(config[subclass_name])
+      end
     end
 
     def analyze(query)
@@ -15,6 +21,12 @@ def analyze(query)
     def save!
       analyzers.each(&:save!)
     end
+
+    class << self
+      def all
+        ObjectSpace.each_object(::Class).select { |c| c < Base }
+      end
+    end
   end
 end
 

scripts/database/query_analyzers.yml

+MultiplePartitionScanDetector:
+  tables:
+    - p_ci_builds
+    - p_ci_builds_metadata
+    - p_ci_job_annotations
+    - p_ci_runner_machine_builds
+  todos:
+    # List query fingerprints which should be ignored until they are fixed.
+    # These fingerprints can be found in the auto_explain pipeline artifacts.
+    # Example:
+    # - c2cfe803a497101b

scripts/database/query_analyzers/base.rb

@@ -7,9 +7,11 @@ class Database
   class QueryAnalyzers
     class Base
       attr_accessor :output
+      attr_reader :config
 
-      def initialize
+      def initialize(config)
         @output = {}
+        @config = config
       end
 
       def filename

scripts/database/query_analyzers/multiple_partition_scan_detector.rb

@@ -5,14 +5,12 @@
 class Database
   class QueryAnalyzers
     class MultiplePartitionScanDetector < Database::QueryAnalyzers::Base
-      TABLES = %w[
-        p_ci_builds p_ci_builds_metadata p_ci_job_annotations p_ci_runner_machine_builds
-      ].freeze
-
       def analyze(query)
         super
 
-        TABLES.each do |table_name|
+        return if config['todos']&.include?(query['fingerprint'])
+
+        config['tables'].each do |table_name|
           if query['query'].include?(table_name) && query['plan'].to_s.include?('"Subplans Removed"=>0')
             (output[table_name] ||= []) << query
           end
@@ -20,7 +18,7 @@ def analyze(query)
       end
 
       def save!
-        TABLES.each do |table_name|
+        config['tables'].each do |table_name|
           next unless output[table_name]
 
           Zlib::GzipWriter.open(output_path("#{table_name}_multiple_partition_scans.ndjson")) do |file|