--- /dev/null
+module ActiveRecord
+ module ConnectionAdapters # :nodoc:
+ module SchemaStatements
+ # Returns a Hash of mappings from the abstract data types to the native
+ # database types. See TableDefinition#column for details on the recognized
+ # abstract data types.
+ def native_database_types
+ {}
+ end
+
+ # This is the maximum length a table alias can be
+ def table_alias_length
+ 255
+ end
+
+ # Truncates a table alias according to the limits of the current adapter.
+ def table_alias_for(table_name)
+ table_name[0..table_alias_length-1].gsub(/\./, '_')
+ end
+
+ # def tables(name = nil) end
+
+ def table_exists?(table_name)
+ tables.include?(table_name.to_s)
+ end
+
+ # Returns an array of indexes for the given table.
+ # def indexes(table_name, name = nil) 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
+
+ # Creates a new table with the name +table_name+. +table_name+ may either
+ # be a String or a Symbol.
+ #
+ # There are two ways to work with +create_table+. You can use the block
+ # form or the regular form, like this:
+ #
+ # === Block form
+ # # create_table() passes a TableDefinition object to the block.
+ # # This form will not only create the table, but also columns for the
+ # # table.
+ # create_table(:suppliers) do |t|
+ # t.column :name, :string, :limit => 60
+ # # Other fields here
+ # end
+ #
+ # === Regular form
+ # # Creates a table called 'suppliers' with no columns.
+ # create_table(:suppliers)
+ # # Add a column to 'suppliers'.
+ # add_column(:suppliers, :name, :string, {:limit => 60})
+ #
+ # The +options+ hash can include the following keys:
+ # [<tt>:id</tt>]
+ # Whether to automatically add a primary key column. Defaults to true.
+ # Join tables for +has_and_belongs_to_many+ should set <tt>:id => false</tt>.
+ # [<tt>:primary_key</tt>]
+ # The name of the primary key, if one is to be added automatically.
+ # Defaults to +id+.
+ # [<tt>:options</tt>]
+ # Any extra options you want appended to the table definition.
+ # [<tt>:temporary</tt>]
+ # Make a temporary table.
+ # [<tt>:force</tt>]
+ # Set to true to drop the table before creating it.
+ # Defaults to false.
+ #
+ # ===== Examples
+ # ====== Add a backend specific option to the generated SQL (MySQL)
+ # create_table(:suppliers, :options => 'ENGINE=InnoDB DEFAULT CHARSET=utf8')
+ # generates:
+ # CREATE TABLE suppliers (
+ # id int(11) DEFAULT NULL auto_increment PRIMARY KEY
+ # ) ENGINE=InnoDB DEFAULT CHARSET=utf8
+ #
+ # ====== Rename the primary key column
+ # create_table(:objects, :primary_key => 'guid') do |t|
+ # t.column :name, :string, :limit => 80
+ # end
+ # generates:
+ # CREATE TABLE objects (
+ # guid int(11) DEFAULT NULL auto_increment PRIMARY KEY,
+ # name varchar(80)
+ # )
+ #
+ # ====== Do not add a primary key column
+ # create_table(:categories_suppliers, :id => false) do |t|
+ # t.column :category_id, :integer
+ # t.column :supplier_id, :integer
+ # end
+ # generates:
+ # CREATE TABLE categories_suppliers (
+ # category_id int,
+ # supplier_id int
+ # )
+ #
+ # See also TableDefinition#column for details on how to create columns.
+ def create_table(table_name, options = {})
+ table_definition = TableDefinition.new(self)
+ table_definition.primary_key(options[:primary_key] || Base.get_primary_key(table_name)) unless options[:id] == false
+
+ yield table_definition
+
+ if options[:force] && table_exists?(table_name)
+ drop_table(table_name, options)
+ end
+
+ create_sql = "CREATE#{' TEMPORARY' if options[:temporary]} TABLE "
+ create_sql << "#{quote_table_name(table_name)} ("
+ create_sql << table_definition.to_sql
+ create_sql << ") #{options[:options]}"
+ execute create_sql
+ end
+
+ # A block for changing columns in +table+.
+ #
+ # === Example
+ # # change_table() yields a Table instance
+ # change_table(:suppliers) do |t|
+ # t.column :name, :string, :limit => 60
+ # # Other column alterations here
+ # end
+ #
+ # ===== Examples
+ # ====== Add a column
+ # change_table(:suppliers) do |t|
+ # t.column :name, :string, :limit => 60
+ # end
+ #
+ # ====== Add 2 integer columns
+ # change_table(:suppliers) do |t|
+ # t.integer :width, :height, :null => false, :default => 0
+ # end
+ #
+ # ====== Add created_at/updated_at columns
+ # change_table(:suppliers) do |t|
+ # t.timestamps
+ # end
+ #
+ # ====== Add a foreign key column
+ # change_table(:suppliers) do |t|
+ # t.references :company
+ # end
+ #
+ # Creates a <tt>company_id(integer)</tt> column
+ #
+ # ====== Add a polymorphic foreign key column
+ # change_table(:suppliers) do |t|
+ # t.belongs_to :company, :polymorphic => true
+ # end
+ #
+ # Creates <tt>company_type(varchar)</tt> and <tt>company_id(integer)</tt> columns
+ #
+ # ====== Remove a column
+ # change_table(:suppliers) do |t|
+ # t.remove :company
+ # end
+ #
+ # ====== Remove several columns
+ # change_table(:suppliers) do |t|
+ # t.remove :company_id
+ # t.remove :width, :height
+ # end
+ #
+ # ====== Remove an index
+ # change_table(:suppliers) do |t|
+ # t.remove_index :company_id
+ # end
+ #
+ # See also Table for details on
+ # all of the various column transformation
+ def change_table(table_name)
+ yield Table.new(table_name, self)
+ end
+
+ # Renames a table.
+ # ===== Example
+ # rename_table('octopuses', 'octopi')
+ def rename_table(table_name, new_name)
+ raise NotImplementedError, "rename_table is not implemented"
+ end
+
+ # Drops a table from the database.
+ def drop_table(table_name, options = {})
+ execute "DROP TABLE #{quote_table_name(table_name)}"
+ end
+
+ # Adds a new column to the named table.
+ # See TableDefinition#column for details of the options you can use.
+ def add_column(table_name, column_name, type, options = {})
+ add_column_sql = "ALTER TABLE #{quote_table_name(table_name)} ADD #{quote_column_name(column_name)} #{type_to_sql(type, options[:limit], options[:precision], options[:scale])}"
+ add_column_options!(add_column_sql, options)
+ execute(add_column_sql)
+ end
+
+ # Removes the column(s) from the table definition.
+ # ===== Examples
+ # remove_column(:suppliers, :qualification)
+ # remove_columns(:suppliers, :qualification, :experience)
+ def remove_column(table_name, *column_names)
+ column_names.flatten.each do |column_name|
+ execute "ALTER TABLE #{quote_table_name(table_name)} DROP #{quote_column_name(column_name)}"
+ end
+ end
+ alias :remove_columns :remove_column
+
+ # Changes the column's definition according to the new options.
+ # See TableDefinition#column for details of the options you can use.
+ # ===== Examples
+ # change_column(:suppliers, :name, :string, :limit => 80)
+ # change_column(:accounts, :description, :text)
+ def change_column(table_name, column_name, type, options = {})
+ raise NotImplementedError, "change_column is not implemented"
+ end
+
+ # Sets a new default value for a column. If you want to set the default
+ # value to +NULL+, you are out of luck. You need to
+ # DatabaseStatements#execute the appropriate SQL statement yourself.
+ # ===== Examples
+ # change_column_default(:suppliers, :qualification, 'new')
+ # change_column_default(:accounts, :authorized, 1)
+ def change_column_default(table_name, column_name, default)
+ raise NotImplementedError, "change_column_default is not implemented"
+ end
+
+ # Renames a column.
+ # ===== Example
+ # rename_column(:suppliers, :description, :name)
+ def rename_column(table_name, column_name, new_column_name)
+ raise NotImplementedError, "rename_column is not implemented"
+ end
+
+ # Adds a new index to the table. +column_name+ can be a single Symbol, or
+ # an Array of Symbols.
+ #
+ # The index will be named after the table and the first column name,
+ # unless you pass <tt>:name</tt> as an option.
+ #
+ # When creating an index on multiple columns, the first column is used as a name
+ # for the index. For example, when you specify an index on two columns
+ # [<tt>:first</tt>, <tt>:last</tt>], the DBMS creates an index for both columns as well as an
+ # index for the first column <tt>:first</tt>. Using just the first name for this index
+ # makes sense, because you will never have to create a singular index with this
+ # name.
+ #
+ # ===== Examples
+ # ====== Creating a simple index
+ # add_index(:suppliers, :name)
+ # generates
+ # CREATE INDEX suppliers_name_index ON suppliers(name)
+ # ====== Creating a unique index
+ # add_index(:accounts, [:branch_id, :party_id], :unique => true)
+ # generates
+ # CREATE UNIQUE INDEX accounts_branch_id_party_id_index ON accounts(branch_id, party_id)
+ # ====== Creating a named index
+ # add_index(:accounts, [:branch_id, :party_id], :unique => true, :name => 'by_branch_party')
+ # generates
+ # CREATE UNIQUE INDEX by_branch_party ON accounts(branch_id, party_id)
+ def add_index(table_name, column_name, options = {})
+ column_names = Array(column_name)
+ index_name = index_name(table_name, :column => column_names)
+
+ if Hash === options # legacy support, since this param was a string
+ index_type = options[:unique] ? "UNIQUE" : ""
+ index_name = options[:name] || index_name
+ else
+ index_type = options
+ end
+ quoted_column_names = column_names.map { |e| quote_column_name(e) }.join(", ")
+ execute "CREATE #{index_type} INDEX #{quote_column_name(index_name)} ON #{quote_table_name(table_name)} (#{quoted_column_names})"
+ end
+
+ # Remove the given index from the table.
+ #
+ # Remove the suppliers_name_index in the suppliers table.
+ # remove_index :suppliers, :name
+ # Remove the index named accounts_branch_id_index in the accounts table.
+ # remove_index :accounts, :column => :branch_id
+ # Remove the index named accounts_branch_id_party_id_index in the accounts table.
+ # remove_index :accounts, :column => [:branch_id, :party_id]
+ # Remove the index named by_branch_party in the accounts table.
+ # remove_index :accounts, :name => :by_branch_party
+ def remove_index(table_name, options = {})
+ execute "DROP INDEX #{quote_column_name(index_name(table_name, options))} ON #{table_name}"
+ end
+
+ def index_name(table_name, options) #:nodoc:
+ if Hash === options # legacy support
+ if options[:column]
+ "index_#{table_name}_on_#{Array(options[:column]) * '_and_'}"
+ elsif options[:name]
+ options[:name]
+ else
+ raise ArgumentError, "You must specify the index name"
+ end
+ else
+ index_name(table_name, :column => options)
+ end
+ end
+
+ # Returns a string of <tt>CREATE TABLE</tt> SQL statement(s) for recreating the
+ # entire structure of the database.
+ def structure_dump
+ end
+
+ def dump_schema_information #:nodoc:
+ sm_table = ActiveRecord::Migrator.schema_migrations_table_name
+ migrated = select_values("SELECT version FROM #{sm_table}")
+ migrated.map { |v| "INSERT INTO #{sm_table} (version) VALUES ('#{v}');" }.join("\n\n")
+ end
+
+ # Should not be called normally, but this operation is non-destructive.
+ # The migrations module handles this automatically.
+ def initialize_schema_migrations_table
+ sm_table = ActiveRecord::Migrator.schema_migrations_table_name
+
+ unless tables.detect { |t| t == sm_table }
+ create_table(sm_table, :id => false) do |schema_migrations_table|
+ schema_migrations_table.column :version, :string, :null => false
+ end
+ add_index sm_table, :version, :unique => true,
+ :name => 'unique_schema_migrations'
+
+ # Backwards-compatibility: if we find schema_info, assume we've
+ # migrated up to that point:
+ si_table = Base.table_name_prefix + 'schema_info' + Base.table_name_suffix
+
+ if tables.detect { |t| t == si_table }
+
+ old_version = select_value("SELECT version FROM #{quote_table_name(si_table)}").to_i
+ assume_migrated_upto_version(old_version)
+ drop_table(si_table)
+ end
+ end
+ end
+
+ def assume_migrated_upto_version(version)
+ version = version.to_i
+ sm_table = quote_table_name(ActiveRecord::Migrator.schema_migrations_table_name)
+
+ migrated = select_values("SELECT version FROM #{sm_table}").map(&:to_i)
+ versions = Dir['db/migrate/[0-9]*_*.rb'].map do |filename|
+ filename.split('/').last.split('_').first.to_i
+ end
+
+ unless migrated.include?(version)
+ execute "INSERT INTO #{sm_table} (version) VALUES ('#{version}')"
+ end
+
+ inserted = Set.new
+ (versions - migrated).each do |v|
+ if inserted.include?(v)
+ raise "Duplicate migration #{v}. Please renumber your migrations to resolve the conflict."
+ elsif v < version
+ execute "INSERT INTO #{sm_table} (version) VALUES ('#{v}')"
+ inserted << v
+ end
+ end
+ end
+
+ def type_to_sql(type, limit = nil, precision = nil, scale = nil) #:nodoc:
+ if native = native_database_types[type]
+ column_type_sql = (native.is_a?(Hash) ? native[:name] : native).dup
+
+ if type == :decimal # ignore limit, use precision and scale
+ scale ||= native[:scale]
+
+ if precision ||= native[:precision]
+ if scale
+ column_type_sql << "(#{precision},#{scale})"
+ else
+ column_type_sql << "(#{precision})"
+ end
+ elsif scale
+ raise ArgumentError, "Error adding decimal column: precision cannot be empty if scale if specified"
+ end
+
+ elsif (type != :primary_key) && (limit ||= native.is_a?(Hash) && native[:limit])
+ column_type_sql << "(#{limit})"
+ end
+
+ column_type_sql
+ else
+ type
+ end
+ end
+
+ def add_column_options!(sql, options) #:nodoc:
+ sql << " DEFAULT #{quote(options[:default], options[:column])}" if options_include_default?(options)
+ # must explicitly check for :null to allow change_column to work on migrations
+ if options[:null] == false
+ sql << " NOT NULL"
+ end
+ end
+
+ # SELECT DISTINCT clause for a given set of columns and a given ORDER BY clause.
+ # Both PostgreSQL and Oracle overrides this for custom DISTINCT syntax.
+ #
+ # distinct("posts.id", "posts.created_at desc")
+ def distinct(columns, order_by)
+ "DISTINCT #{columns}"
+ end
+
+ # ORDER BY clause for the passed order option.
+ # PostgreSQL overrides this due to its stricter standards compliance.
+ def add_order_by_for_association_limiting!(sql, options)
+ sql << " ORDER BY #{options[:order]}"
+ end
+
+ # Adds timestamps (created_at and updated_at) columns to the named table.
+ # ===== Examples
+ # add_timestamps(:suppliers)
+ def add_timestamps(table_name)
+ add_column table_name, :created_at, :datetime
+ add_column table_name, :updated_at, :datetime
+ end
+
+ # Removes the timestamp columns (created_at and updated_at) from the table definition.
+ # ===== Examples
+ # remove_timestamps(:suppliers)
+ def remove_timestamps(table_name)
+ remove_column table_name, :updated_at
+ remove_column table_name, :created_at
+ end
+
+ protected
+ def options_include_default?(options)
+ options.include?(:default) && !(options[:null] == false && options[:default].nil?)
+ end
+ end
+ end
+end
projects / depot.git / blobdiff