lib/index_shotgun/analyzer.rb in index_shotgun-0.1.0.beta1 vs lib/index_shotgun/analyzer.rb in index_shotgun-0.1.0.beta2

@@ -3,35 +3,58 @@
     require "index_shotgun/array_start_with"
 
     class << self
       using IndexShotgun::ArrayStartWith
 
+      # Search duplicate index
+      # @return [String] result message
+      def perform
+        tables = ActiveRecord::Base.connection.tables
+
+        duplicate_indexes =
+          tables.each_with_object([]) do |table, array|
+            response = check_indexes(table)
+            array.push(*response)
+          end
+
+        duplicate_indexes.each_with_object("") do |info, message|
+          message << <<-EOS.strip_heredoc
+            # =============================
+            # #{info[:index].table}
+            # =============================
+
+            # #{info[:result]}
+            # To remove this duplicate index, execute:
+            ALTER TABLE `#{info[:index].table}` DROP INDEX `#{info[:index].name}`;
+
+          EOS
+        end
+      end
+
+      # check duplicate indexes of table
+      # @param table [String] table name
+      # @return [Array<Hash>] array of index info
+      #   index: index info {ActiveRecord::ConnectionAdapters::IndexDefinition}
+      #   result: search result message
       def check_indexes(table)
         indexes = table_indexes(table)
 
-        response = []
-        indexes.each do |source_index|
-          indexes.each do |target_index|
-            next if source_index.name == target_index.name
+        indexes.permutation(2).each_with_object([]) do |(source_index, target_index), response|
+          next unless source_index.columns.start_with?(target_index.columns)
 
-            if source_index.columns.start_with?(target_index.columns)
-              if target_index.unique
-                last_column = source_index.columns.last
-                response << {
-                  index:  source_index,
-                  result: "#{source_index.name} has unnecessary column #{last_column} (#{target_index.name} is unique index!)",
-                }
-              else
-                response << {
-                  index:  target_index,
-                  result: "#{target_index.name} is a left-prefix of #{source_index.name}",
-                }
-              end
-            end
+          if target_index.unique
+            last_column = source_index.columns.last
+            response << {
+              index:  source_index,
+              result: "#{source_index.name} has unnecessary column #{last_column} (#{target_index.name} is unique index!)",
+            }
+          else
+            response << {
+              index:  target_index,
+              result: "#{target_index.name} is a left-prefix of #{source_index.name}",
+            }
           end
         end
-
-        response
       end
 
       # get indexes of table
       # @param table [String]
       # @see [ActiveRecord::ConnectionAdapters::TableDefinition#indexes]