# sqlite_adapter.rb
# author: Luke Holden <lholden@cablelan.net>
require 'active_record/connection_adapters/abstract_adapter'
module ActiveRecord
class Base
# Establishes a connection to the database that's used by all Active Record objects
def self.sqlite_connection(config) # :nodoc:
require_library_or_gem('sqlite') unless self.class.const_defined?(:SQLite)
symbolize_strings_in_hash(config)
unless config.has_key?(:dbfile)
raise ArgumentError, "No database file specified. Missing argument: dbfile"
end
config[:dbfile] = File.expand_path(config[:dbfile], RAILS_ROOT) if Object.const_defined?(:RAILS_ROOT)
db = SQLite::Database.new(config[:dbfile], 0)
db.show_datatypes = "ON" if !defined? SQLite::Version
db.results_as_hash = true if defined? SQLite::Version
db.type_translation = false
ConnectionAdapters::SQLiteAdapter.new(db, logger)
end
end
module ConnectionAdapters
class SQLiteAdapter < AbstractAdapter # :nodoc:
def select_all(sql, name = nil)
select(sql, name)
end
def select_one(sql, name = nil)
result = select(sql, name)
result.nil? ? nil : result.first
end
def columns(table_name, name = nil)
table_structure(table_name).inject([]) do |columns, field|
columns << Column.new(field['name'], field['dflt_value'], field['type'])
columns
end
end
def insert(sql, name = nil, pk = nil, id_value = nil)
execute(sql, name = nil)
id_value || @connection.send( defined?( SQLite::Version ) ? :last_insert_row_id : :last_insert_rowid )
end
def execute(sql, name = nil)
log(sql, name, @connection) do |connection|
if defined?( SQLite::Version )
case sql
when "BEGIN" then connection.transaction
when "COMMIT" then connection.commit
when "ROLLBACK" then connection.rollback
else connection.execute(sql)
end
else
connection.execute( sql )
end
end
end
def update(sql, name = nil)
execute(sql, name)
@connection.changes
end
def delete(sql, name = nil)
sql += " WHERE 1=1" unless sql =~ /WHERE/i
execute(sql, name)
@connection.changes
end
def begin_db_transaction() execute "BEGIN" end
def commit_db_transaction() execute "COMMIT" end
def rollback_db_transaction() execute "ROLLBACK" end
def quote_string(s)
SQLite::Database.quote(s)
end
def quote_column_name(name)
return "'#{name}'"
end
private
def select(sql, name = nil)
results = nil
log(sql, name, @connection) { |connection| results = connection.execute(sql) }
rows = []
results.each do |row|
hash_only_row = {}
row.each_key do |key|
hash_only_row[key.sub(/\w+\./, "")] = row[key] unless key.class == Fixnum
end
rows << hash_only_row
end
return rows
end
def table_structure(table_name)
sql = "PRAGMA table_info(#{table_name});"
results = nil
log(sql, nil, @connection) { |connection| results = connection.execute(sql) }
return results
end
end
end
end