r3616@asus: jeremy | 2005-09-26 23:09:28 -0700

 Ticket 2292 - Sequences, schemas, and fixtures
 r3917@asus:  jeremy | 2005-10-15 10:43:24 -0700
 fix pk assert
 r3918@asus:  jeremy | 2005-10-15 10:46:52 -0700
 rework query cache connection= override
 r3919@asus:  jeremy | 2005-10-15 10:47:45 -0700
 correct fixtures usage
 r3920@asus:  jeremy | 2005-10-15 10:53:23 -0700
 correct attr assignment
 r3921@asus:  jeremy | 2005-10-15 12:59:10 -0700
 sequences
 r3922@asus:  jeremy | 2005-10-15 16:36:09 -0700
 reset fixtures work with sequences
 r3951@asus:  jeremy | 2005-10-15 23:23:12 -0700
 cut down excess features
 r3952@asus:  jeremy | 2005-10-15 23:40:30 -0700
 don't test for PostgreSQL specifically


git-svn-id: http://svn-commit.rubyonrails.org/rails/trunk@2639 5ecf4fe2-1ee6-0310-87b1-e25e094e27de

7 files changed, 78 insertions, 36 deletions

diff --git a/activerecord/lib/active_record/base.rb b/activerecord/lib/active_record/base.rb
index 48d9c6ae12..58f884595c 100755
--- a/activerecord/lib/active_record/base.rb
+++ b/activerecord/lib/active_record/base.rb
@@ -625,9 +625,9 @@ module ActiveRecord #:nodoc:
         "type"
       end
 
-      # Defines the sequence_name (for Oracle) -- can be overridden in subclasses.
+      # Default sequence_name.  Use set_sequence_name to override.
       def sequence_name
-        "#{table_name}_seq"
+        connection.default_sequence_name(table_name, primary_key)
       end
 
       # Sets the table name to use to the given value, or (if the value
@@ -675,8 +675,8 @@ module ActiveRecord #:nodoc:
 
       # Sets the name of the sequence to use when generating ids to the given
       # value, or (if the value is nil or false) to the value returned by the
-      # given block. Currently useful only when using Oracle, which requires
-      # explicit sequences.
+      # given block. This is required for Oracle and is useful for any
+      # database which relies on sequences for primary key generation.
       #
       # Setting the sequence name when using other dbs will have no effect.
       # If a sequence name is not explicitly set when using Oracle, it will
diff --git a/activerecord/lib/active_record/connection_adapters/abstract/connection_specification.rb b/activerecord/lib/active_record/connection_adapters/abstract/connection_specification.rb
index b5ddef32af..eab61085e3 100644
--- a/activerecord/lib/active_record/connection_adapters/abstract/connection_specification.rb
+++ b/activerecord/lib/active_record/connection_adapters/abstract/connection_specification.rb
@@ -114,9 +114,15 @@ module ActiveRecord
 
     # Set the connection for the class.
     def self.connection=(spec)
-      raise ConnectionNotEstablished unless spec
-      conn = self.send(spec.adapter_method, spec.config)
-      active_connections[self] = conn
+      if spec.kind_of?(ActiveRecord::ConnectionAdapters::AbstractAdapter)
+        active_connections[self] = spec
+      elsif spec.kind_of?(ConnectionSpecification)
+        self.connection = self.send(spec.adapter_method, spec.config)
+      elsif spec.nil?
+        raise ConnectionNotEstablished
+      else
+        establish_connection spec
+      end
     end
   end
 end
diff --git a/activerecord/lib/active_record/connection_adapters/abstract/database_statements.rb b/activerecord/lib/active_record/connection_adapters/abstract/database_statements.rb
index 90dc951b6d..c45454eacc 100644
--- a/activerecord/lib/active_record/connection_adapters/abstract/database_statements.rb
+++ b/activerecord/lib/active_record/connection_adapters/abstract/database_statements.rb
@@ -90,6 +90,15 @@ module ActiveRecord
           end
         end
       end
+
+      def default_sequence_name(table, column)
+        nil
+      end
+
+      # Set the sequence to the max value of the table's column.
+      def reset_sequence!(table, column, sequence = nil)
+        # Do nothing by default.  Implement for PostgreSQL, Oracle, ...
+      end
     end
   end
 end
diff --git a/activerecord/lib/active_record/connection_adapters/oci_adapter.rb b/activerecord/lib/active_record/connection_adapters/oci_adapter.rb
index 194e5d0062..9897403797 100644
--- a/activerecord/lib/active_record/connection_adapters/oci_adapter.rb
+++ b/activerecord/lib/active_record/connection_adapters/oci_adapter.rb
@@ -99,6 +99,10 @@ begin
       # * <tt>:password</tt> -- Defaults to nothing
       # * <tt>:host</tt> -- Defaults to localhost
       class OCIAdapter < AbstractAdapter
+        def default_sequence_name(table, column)
+          "#{table}_seq"
+        end
+
         def quote_string(string)
           string.gsub(/'/, "''")
         end
diff --git a/activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb b/activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb
index e7bedaee9e..203d390046 100644
--- a/activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb
+++ b/activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb
@@ -102,7 +102,7 @@ module ActiveRecord
       def insert(sql, name = nil, pk = nil, id_value = nil, sequence_name = nil) #:nodoc:
         execute(sql, name)
         table = sql.split(" ", 4)[2]
-        id_value || last_insert_id(table, pk)
+        id_value || last_insert_id(table, sequence_name)
       end
 
       def query(sql, name = nil) #:nodoc:
@@ -198,6 +198,37 @@ module ActiveRecord
       def schema_search_path #:nodoc:
         @schema_search_path ||= query('SHOW search_path')[0][0]
       end
+
+      def default_sequence_name(table_name, pk = 'id')
+        "#{table_name}_#{pk}_seq"
+      end
+
+      # Set the sequence to the max value of the table's pk.
+      def reset_pk_sequence!(table)
+        sequence, pk = sequence_and_pk_for(table)
+        if sequence and pk
+          select_value <<-end_sql, 'Reset sequence'
+            SELECT setval('#{sequence}', (SELECT COALESCE(MAX(#{pk})+(SELECT increment_by FROM #{sequence}), (SELECT min_value FROM #{sequence})) FROM #{table}), false)
+          end_sql
+        end
+      end
+
+      # Find a table's primary key and sequence.
+      def sequence_and_pk_for(table, column = nil)
+        execute(<<-end_sql, 'Find pk sequence')[0]
+          SELECT (name.nspname || '.' || seq.relname) AS sequence, attr.attname AS pk
+          FROM pg_class seq, pg_attribute attr, pg_depend dep, pg_namespace name, pg_constraint cons
+          WHERE seq.oid = dep.objid
+            AND seq.relnamespace = name.oid
+            AND attr.attrelid = dep.refobjid
+            AND attr.attnum = dep.refobjsubid
+            AND attr.attrelid = cons.conrelid
+            AND attr.attnum = cons.conkey[1]
+            AND cons.contype = 'p'
+            AND dep.refobjid = '#{table}'::regclass
+        end_sql
+      end
+
       
       def rename_table(name, new_name)
         execute "ALTER TABLE #{name} RENAME TO #{new_name}"
@@ -242,9 +273,10 @@ module ActiveRecord
       private
         BYTEA_COLUMN_TYPE_OID = 17
 
-        def last_insert_id(table, column = nil)
-          sequence_name = "#{table}_#{column || 'id'}_seq"
-          @connection.exec("SELECT currval('#{sequence_name}')")[0][0].to_i
+        def last_insert_id(table, sequence_name)
+          if sequence_name
+            @connection.exec("SELECT currval('#{sequence_name}')")[0][0].to_i
+          end
         end
 
         def select(sql, name = nil)
diff --git a/activerecord/lib/active_record/fixtures.rb b/activerecord/lib/active_record/fixtures.rb
index 6ee963951e..ef4757fcee 100755
--- a/activerecord/lib/active_record/fixtures.rb
+++ b/activerecord/lib/active_record/fixtures.rb
@@ -257,8 +257,13 @@ class Fixtures < YAML::Omap
         fixtures.reverse.each { |fixture| fixture.delete_existing_fixtures }
         fixtures.each { |fixture| fixture.insert_fixtures }
       end
-      
-      reset_sequences(connection, table_names) if connection.is_a?(ActiveRecord::ConnectionAdapters::PostgreSQLAdapter)
+
+      # Cap primary key sequences to max(pk).
+      if connection.respond_to?(:reset_pk_sequence!)
+        table_names.flatten.each do |table_name|
+          connection.reset_pk_sequence!(table_name)
+        end
+      end
 
       return fixtures.size > 1 ? fixtures : fixtures.first
     ensure
@@ -266,21 +271,6 @@ class Fixtures < YAML::Omap
     end
   end
 
-  # Start PostgreSQL fixtures at id 1.  Skip tables without models
-  # and models with nonstandard primary keys.
-  def self.reset_sequences(connection, table_names)
-    table_names.flatten.each do |table|
-      if table_class = table.to_s.classify.constantize rescue nil
-        pk = table_class.columns_hash[table_class.primary_key]
-        if pk and pk.type == :integer
-          connection.execute(
-            "SELECT setval('#{table}_#{pk.name}_seq', (SELECT COALESCE(MAX(#{pk.name}), 0)+1 FROM #{table}), false)", 
-            'Setting Sequence'
-          )
-        end
-      end
-    end
-  end
 
   attr_reader :table_name
 
diff --git a/activerecord/lib/active_record/query_cache.rb b/activerecord/lib/active_record/query_cache.rb
index 794caff59c..e79b3e05a7 100644
--- a/activerecord/lib/active_record/query_cache.rb
+++ b/activerecord/lib/active_record/query_cache.rb
@@ -44,14 +44,15 @@ module ActiveRecord
   
   class Base
     # Set the connection for the class with caching on
-    def self.connection=(spec)
-      raise ConnectionNotEstablished unless spec
-
-      conn = spec.config[:query_cache] ?
-        QueryCache.new(self.send(spec.adapter_method, spec.config)) :
-        self.send(spec.adapter_method, spec.config)
-      
-      active_connections[self] = conn
+    class << self
+      alias_method :connection_without_query_cache=, :connection=
+
+      def connection=(spec)
+        if spec.is_a?(ConnectionSpecification) and spec.config[:query_cache]
+          spec = QueryCache.new(self.send(spec.adapter_method, spec.config))
+        end
+        self.connection_without_query_cache = spec
+      end
     end
   end