From 11ff3da5f4fe71a8d93180ab9fa69c6190a2e26e Mon Sep 17 00:00:00 2001 From: Andrew White Date: Thu, 18 Mar 2010 16:49:23 +0000 Subject: Add column and index query methods to ActiveRecord::Schema MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit [#4219 state:resolved] Signed-off-by: José Valim --- .../abstract/schema_definitions.rb | 10 ++++ .../abstract/schema_statements.rb | 57 ++++++++++++++++++++-- 2 files changed, 63 insertions(+), 4 deletions(-) (limited to 'activerecord/lib/active_record/connection_adapters') diff --git a/activerecord/lib/active_record/connection_adapters/abstract/schema_definitions.rb b/activerecord/lib/active_record/connection_adapters/abstract/schema_definitions.rb index 7d58bc2adf..7691b6a788 100644 --- a/activerecord/lib/active_record/connection_adapters/abstract/schema_definitions.rb +++ b/activerecord/lib/active_record/connection_adapters/abstract/schema_definitions.rb @@ -582,6 +582,11 @@ module ActiveRecord @base.add_column(@table_name, column_name, type, options) end + # Checks to see if a column exists. See SchemaStatements#column_exists? + def column_exists?(column_name, type = nil, options = nil) + @base.column_exists?(@table_name, column_name, type, options) + end + # Adds a new index to the table. +column_name+ can be a single Symbol, or # an Array of Symbols. See SchemaStatements#add_index # @@ -596,6 +601,11 @@ module ActiveRecord @base.add_index(@table_name, column_name, options) end + # Checks to see if an index exists. See SchemaStatements#index_exists? + def index_exists?(column_name, options = {}) + @base.index_exists?(@table_name, column_name, options) + end + # Adds timestamps (created_at and updated_at) columns to the table. See SchemaStatements#add_timestamps # ===== Example # t.timestamps diff --git a/activerecord/lib/active_record/connection_adapters/abstract/schema_statements.rb b/activerecord/lib/active_record/connection_adapters/abstract/schema_statements.rb index 638e5d7236..5625dba45f 100644 --- a/activerecord/lib/active_record/connection_adapters/abstract/schema_statements.rb +++ b/activerecord/lib/active_record/connection_adapters/abstract/schema_statements.rb @@ -24,10 +24,59 @@ module ActiveRecord # Returns an array of indexes for the given table. # def indexes(table_name, name = nil) end + # Checks to see if an index exists on a table for a given index definition + # + # === Examples + # # Check an index exists + # index_exists?(:suppliers, :company_id) + # + # # Check an index on multiple columns exists + # index_exists?(:suppliers, [:company_id, :company_type]) + # + # # Check a unique index exists + # index_exists?(:suppliers, :company_id, :unique => true) + # + # # Check an index with a custom name exists + # index_exists?(:suppliers, :company_id, :name => "idx_company_id" + def index_exists?(table_name, column_name, options = {}) + column_names = Array.wrap(column_name) + index_name = options.key?(:name) ? options[:name].to_s : index_name(table_name, :column => column_names) + if options[:unique] + indexes(table_name).any?{ |i| i.unique && i.name == index_name } + else + indexes(table_name).any?{ |i| i.name == index_name } + end + end + # Returns an array of Column objects for the table specified by +table_name+. # See the concrete implementation for details on the expected parameter values. def columns(table_name, name = nil) end + # Checks to see if a column exists in a given table. + # + # === Examples + # # Check a column exists + # column_exists?(:suppliers, :name) + # + # # Check a column exists of a particular type + # column_exists?(:suppliers, :name, :string) + # + # # Check a column exists with a specific definition + # column_exists?(:suppliers, :name, :string, :limit => 100) + def column_exists?(table_name, column_name, type = nil, options = nil) + column_name = column_name.to_s + if type + if options + sql_type = type_to_sql(type, options[:limit], options[:precision], options[:scale]) + columns(table_name).any?{ |c| c.name == column_name && c.sql_type == sql_type } + else + columns(table_name).any?{ |c| c.name == column_name && c.type == type } + end + else + columns(table_name).any?{ |c| c.name == column_name } + end + end + # Creates a new table with the name +table_name+. +table_name+ may either # be a String or a Symbol. # @@ -293,7 +342,7 @@ module ActiveRecord @logger.warn("Index name '#{index_name}' on table '#{table_name}' is too long; the limit is #{index_name_length} characters. Skipping.") return end - if index_exists?(table_name, index_name, false) + if index_name_exists?(table_name, index_name, false) @logger.warn("Index name '#{index_name}' on table '#{table_name}' already exists. Skipping.") return end @@ -314,7 +363,7 @@ module ActiveRecord # remove_index :accounts, :name => :by_branch_party def remove_index(table_name, options = {}) index_name = index_name(table_name, options) - unless index_exists?(table_name, index_name, true) + unless index_name_exists?(table_name, index_name, true) @logger.warn("Index name '#{index_name}' on table '#{table_name}' does not exist. Skipping.") return end @@ -351,11 +400,11 @@ module ActiveRecord end end - # Verify the existence of an index. + # Verify the existence of an index with a given name. # # The default argument is returned if the underlying implementation does not define the indexes method, # as there's no way to determine the correct answer in that case. - def index_exists?(table_name, index_name, default) + def index_name_exists?(table_name, index_name, default) return default unless respond_to?(:indexes) indexes(table_name).detect { |i| i.name == index_name } end -- cgit v1.2.3