From d496055b5b75387136bcdd1cc93aeab14dbda606 Mon Sep 17 00:00:00 2001 From: Ryuta Kamizono Date: Thu, 25 Oct 2018 07:29:51 +0900 Subject: Support expression indexes for MySQL MySQL 8.0.13 and higher supports functional key parts that index expression values rather than column or column prefix values. https://dev.mysql.com/doc/refman/8.0/en/create-index.html --- .../connection_adapters/abstract_mysql_adapter.rb | 4 +++ .../connection_adapters/mysql/schema_statements.rb | 34 +++++++++++++++++++--- 2 files changed, 34 insertions(+), 4 deletions(-) (limited to 'activerecord/lib') diff --git a/activerecord/lib/active_record/connection_adapters/abstract_mysql_adapter.rb b/activerecord/lib/active_record/connection_adapters/abstract_mysql_adapter.rb index 0f73641369..13c799b64a 100644 --- a/activerecord/lib/active_record/connection_adapters/abstract_mysql_adapter.rb +++ b/activerecord/lib/active_record/connection_adapters/abstract_mysql_adapter.rb @@ -72,6 +72,10 @@ module ActiveRecord !mariadb? && version >= "8.0.1" end + def supports_expression_index? + !mariadb? && version >= "8.0.13" + end + def supports_transaction_isolation? true end diff --git a/activerecord/lib/active_record/connection_adapters/mysql/schema_statements.rb b/activerecord/lib/active_record/connection_adapters/mysql/schema_statements.rb index e167c01802..65e9a1fda5 100644 --- a/activerecord/lib/active_record/connection_adapters/mysql/schema_statements.rb +++ b/activerecord/lib/active_record/connection_adapters/mysql/schema_statements.rb @@ -35,13 +35,39 @@ module ActiveRecord ] end - indexes.last[-2] << row[:Column_name] - indexes.last[-1][:lengths][row[:Column_name]] = row[:Sub_part].to_i if row[:Sub_part] - indexes.last[-1][:orders].merge!(row[:Column_name] => :desc) if row[:Collation] == "D" + if row[:Expression] + expression = row[:Expression] + expression = +"(#{expression})" unless expression.start_with?("(") + indexes.last[-2] << expression + indexes.last[-1][:expressions] ||= {} + indexes.last[-1][:expressions][expression] = expression + indexes.last[-1][:orders][expression] = :desc if row[:Collation] == "D" + else + indexes.last[-2] << row[:Column_name] + indexes.last[-1][:lengths][row[:Column_name]] = row[:Sub_part].to_i if row[:Sub_part] + indexes.last[-1][:orders][row[:Column_name]] = :desc if row[:Collation] == "D" + end end end - indexes.map { |index| IndexDefinition.new(*index) } + indexes.map do |index| + options = index.last + + if expressions = options.delete(:expressions) + orders = options.delete(:orders) + lengths = options.delete(:lengths) + + columns = index[-2].map { |name| + [ name.to_sym, expressions[name] || +quote_column_name(name) ] + }.to_h + + index[-2] = add_options_for_index_columns( + columns, order: orders, length: lengths + ).values.join(", ") + end + + IndexDefinition.new(*index) + end end def remove_column(table_name, column_name, type = nil, options = {}) -- cgit v1.2.3