# sybase_adapter.rb
# Author: John R. Sheets
#
# 01 Mar 2006: Initial version. Based on code from Will Sobel
# (http://dev.rubyonrails.org/ticket/2030)
#
# 17 Mar 2006: Added support for migrations; fixed issues with :boolean columns.
#
# 13 Apr 2006: Improved column type support to properly handle dates and user-defined
# types; fixed quoting of integer columns.
#
# 05 Jan 2007: Updated for Rails 1.2 release:
# restricted Fixtures#insert_fixtures monkeypatch to Sybase adapter;
# removed SQL type precision from TEXT type to fix broken
# ActiveRecordStore (jburks, #6878); refactored select() to use execute();
# fixed leaked exception for no-op change_column(); removed verbose SQL dump
# from columns(); added missing scale parameter in normalize_type().
require 'active_record/connection_adapters/abstract_adapter'
begin
require 'sybsql'
module ActiveRecord
class Base
# Establishes a connection to the database that's used by all Active Record objects
def self.sybase_connection(config) # :nodoc:
config = config.symbolize_keys
username = config[:username] ? config[:username].to_s : 'sa'
password = config[:password] ? config[:password].to_s : ''
if config.has_key?(:host)
host = config[:host]
else
raise ArgumentError, "No database server name specified. Missing argument: host."
end
if config.has_key?(:database)
database = config[:database]
else
raise ArgumentError, "No database specified. Missing argument: database."
end
ConnectionAdapters::SybaseAdapter.new(
SybSQL.new({'S' => host, 'U' => username, 'P' => password},
ConnectionAdapters::SybaseAdapterContext), database, config, logger)
end
end # class Base
module ConnectionAdapters
# ActiveRecord connection adapter for Sybase Open Client bindings
# (see http://raa.ruby-lang.org/project/sybase-ctlib).
#
# Options:
#
# * :host -- The name of the database server. No default, must be provided.
# * :database -- The name of the database. No default, must be provided.
# * :username -- Defaults to "sa".
# * :password -- Defaults to empty string.
#
# Usage Notes:
#
# * The sybase-ctlib bindings do not support the DATE SQL column type; use DATETIME instead.
# * Table and column names are limited to 30 chars in Sybase 12.5
# * :binary columns not yet supported
# * :boolean columns use the BIT SQL type, which does not allow nulls or
# indexes. If a DEFAULT is not specified for ALTER TABLE commands, the
# column will be declared with DEFAULT 0 (false).
#
# Migrations:
#
# The Sybase adapter supports migrations, but for ALTER TABLE commands to
# work, the database must have the database option 'select into' set to
# 'true' with sp_dboption (see below). The sp_helpdb command lists the current
# options for all databases.
#
# 1> use mydb
# 2> go
# 1> master..sp_dboption mydb, "select into", true
# 2> go
# 1> checkpoint
# 2> go
class SybaseAdapter < AbstractAdapter # :nodoc:
class ColumnWithIdentity < Column
attr_reader :identity
def initialize(name, default, sql_type = nil, nullable = nil, identity = nil, primary = nil)
super(name, default, sql_type, nullable)
@default, @identity, @primary = type_cast(default), identity, primary
end
def simplified_type(field_type)
case field_type
when /int|bigint|smallint|tinyint/i then :integer
when /float|double|real/i then :float
when /decimal|money|numeric|smallmoney/i then :decimal
when /text|ntext/i then :text
when /binary|image|varbinary/i then :binary
when /char|nchar|nvarchar|string|varchar/i then :string
when /bit/i then :boolean
when /datetime|smalldatetime/i then :datetime
else super
end
end
def self.string_to_binary(value)
"0x#{value.unpack("H*")[0]}"
end
def self.binary_to_string(value)
# FIXME: sybase-ctlib uses separate sql method for binary columns.
value
end
end # class ColumnWithIdentity
# Sybase adapter
def initialize(connection, database, config = {}, logger = nil)
super(connection, logger)
context = connection.context
context.init(logger)
@config = config
@numconvert = config.has_key?(:numconvert) ? config[:numconvert] : true
@limit = @offset = 0
unless connection.sql_norow("USE #{database}")
raise "Cannot USE #{database}"
end
end
def native_database_types
{
:primary_key => "numeric(9,0) IDENTITY PRIMARY KEY",
:string => { :name => "varchar", :limit => 255 },
:text => { :name => "text" },
:integer => { :name => "int" },
:float => { :name => "float", :limit => 8 },
:decimal => { :name => "decimal" },
:datetime => { :name => "datetime" },
:timestamp => { :name => "timestamp" },
:time => { :name => "time" },
:date => { :name => "datetime" },
:binary => { :name => "image"},
:boolean => { :name => "bit" }
}
end
def type_to_sql(type, limit = nil, precision = nil, scale = nil) #:nodoc:
return super unless type.to_s == 'integer'
if !limit.nil? && limit < 4
'smallint'
else
'integer'
end
end
def adapter_name
'Sybase'
end
def active?
!(@connection.connection.nil? || @connection.connection_dead?)
end
def disconnect!
@connection.close rescue nil
end
def reconnect!
raise "Sybase Connection Adapter does not yet support reconnect!"
# disconnect!
# connect! # Not yet implemented
end
def table_alias_length
30
end
def insert_sql(sql, name = nil, pk = nil, id_value = nil, sequence_name = nil)
begin
table_name = get_table_name(sql)
col = get_identity_column(table_name)
ii_enabled = false
if col != nil
if query_contains_identity_column(sql, col)
begin
enable_identity_insert(table_name, true)
ii_enabled = true
rescue Exception => e
raise ActiveRecordError, "IDENTITY_INSERT could not be turned ON"
end
end
end
log(sql, name) do
super || select_value("SELECT @@IDENTITY AS last_id")
end
ensure
if ii_enabled
begin
enable_identity_insert(table_name, false)
rescue Exception => e
raise ActiveRecordError, "IDENTITY_INSERT could not be turned OFF"
end
end
end
end
def execute(sql, name = nil)
raw_execute(sql, name)
@connection.results[0].row_count
end
def begin_db_transaction() raw_execute "BEGIN TRAN" end
def commit_db_transaction() raw_execute "COMMIT TRAN" end
def rollback_db_transaction() raw_execute "ROLLBACK TRAN" end
def current_database
select_value("select DB_NAME() as name")
end
def tables(name = nil)
select("select name from sysobjects where type='U'", name).map { |row| row['name'] }
end
def indexes(table_name, name = nil)
select("exec sp_helpindex #{table_name}", name).map do |index|
unique = index["index_description"] =~ /unique/
primary = index["index_description"] =~ /^clustered/
if !primary
cols = index["index_keys"].split(", ").each { |col| col.strip! }
IndexDefinition.new(table_name, index["index_name"], unique, cols)
end
end.compact
end
def columns(table_name, name = nil)
sql = <= 128
primary = (sysstat2 & 8) == 8
ColumnWithIdentity.new(name, default_value, type, nullable, identity, primary)
end
end
def quoted_true
"1"
end
def quoted_false
"0"
end
def quote(value, column = nil)
return value.quoted_id if value.respond_to?(:quoted_id)
case value
when String
if column && column.type == :binary && column.class.respond_to?(:string_to_binary)
"#{quote_string(column.class.string_to_binary(value))}"
elsif @numconvert && force_numeric?(column) && value =~ /^[+-]?[0-9]+$/o
value
else
"'#{quote_string(value)}'"
end
when NilClass then (column && column.type == :boolean) ? '0' : "NULL"
when TrueClass then '1'
when FalseClass then '0'
when Float, Fixnum, Bignum then force_numeric?(column) ? value.to_s : "'#{value.to_s}'"
else
if value.acts_like?(:time)
"'#{value.strftime("%Y-%m-%d %H:%M:%S")}'"
else
super
end
end
end
# True if column is explicitly declared non-numeric, or
# if column is nil (not specified).
def force_numeric?(column)
(column.nil? || [:integer, :float, :decimal].include?(column.type))
end
def quote_string(s)
s.gsub(/'/, "''") # ' (for ruby-mode)
end
def quote_column_name(name)
# If column name is close to max length, skip the quotes, since they
# seem to count as part of the length.
((name.to_s.length + 2) <= table_alias_length) ? "[#{name}]" : name.to_s
end
def add_limit_offset!(sql, options) # :nodoc:
@limit = options[:limit]
@offset = options[:offset]
if use_temp_table?
# Use temp table to hack offset with Sybase
sql.sub!(/ FROM /i, ' INTO #artemp FROM ')
elsif zero_limit?
# "SET ROWCOUNT 0" turns off limits, so we have
# to use a cheap trick.
if sql =~ /WHERE/i
sql.sub!(/WHERE/i, 'WHERE 1 = 2 AND ')
elsif sql =~ /ORDER\s+BY/i
sql.sub!(/ORDER\s+BY/i, 'WHERE 1 = 2 ORDER BY')
else
sql << 'WHERE 1 = 2'
end
end
end
def add_lock!(sql, options) #:nodoc:
@logger.info "Warning: Sybase :lock option '#{options[:lock].inspect}' not supported" if @logger && options.has_key?(:lock)
sql
end
def supports_migrations? #:nodoc:
true
end
def rename_table(name, new_name)
execute "EXEC sp_rename '#{name}', '#{new_name}'"
end
def rename_column(table, column, new_column_name)
execute "EXEC sp_rename '#{table}.#{column}', '#{new_column_name}'"
end
def change_column(table_name, column_name, type, options = {}) #:nodoc:
begin
execute "ALTER TABLE #{table_name} MODIFY #{column_name} #{type_to_sql(type, options[:limit])}"
rescue StatementInvalid => e
# Swallow exception and reset context if no-op.
raise e unless e.message =~ /no columns to drop, add or modify/
@connection.context.reset
end
if options.has_key?(:default)
remove_default_constraint(table_name, column_name)
execute "ALTER TABLE #{table_name} REPLACE #{column_name} DEFAULT #{quote options[:default]}"
end
end
def remove_column(table_name, column_name)
remove_default_constraint(table_name, column_name)
execute "ALTER TABLE #{table_name} DROP #{column_name}"
end
def remove_default_constraint(table_name, column_name)
sql = "select def.name from sysobjects def, syscolumns col, sysobjects tab where col.cdefault = def.id and col.name = '#{column_name}' and tab.name = '#{table_name}' and col.id = tab.id"
select(sql).each do |constraint|
execute "ALTER TABLE #{table_name} DROP CONSTRAINT #{constraint["name"]}"
end
end
def remove_index(table_name, options = {})
execute "DROP INDEX #{table_name}.#{index_name(table_name, options)}"
end
def add_column_options!(sql, options) #:nodoc:
sql << " DEFAULT #{quote(options[:default], options[:column])}" if options_include_default?(options)
if check_null_for_column?(options[:column], sql)
sql << (options[:null] == false ? " NOT NULL" : " NULL")
end
sql
end
def enable_identity_insert(table_name, enable = true)
if has_identity_column(table_name)
execute "SET IDENTITY_INSERT #{table_name} #{enable ? 'ON' : 'OFF'}"
end
end
private
def check_null_for_column?(col, sql)
# Sybase columns are NOT NULL by default, so explicitly set NULL
# if :null option is omitted. Disallow NULLs for boolean.
type = col.nil? ? "" : col[:type]
# Ignore :null if a primary key
return false if type =~ /PRIMARY KEY/i
# Ignore :null if a :boolean or BIT column
if (sql =~ /\s+bit(\s+DEFAULT)?/i) || type == :boolean
# If no default clause found on a boolean column, add one.
sql << " DEFAULT 0" if $1.nil?
return false
end
true
end
# Return the last value of the identity global value.
def last_insert_id
@connection.sql("SELECT @@IDENTITY")
unless @connection.cmd_fail?
id = @connection.top_row_result.rows.first.first
if id
id = id.to_i
id = nil if id == 0
end
else
id = nil
end
id
end
def affected_rows(name = nil)
@connection.sql("SELECT @@ROWCOUNT")
unless @connection.cmd_fail?
count = @connection.top_row_result.rows.first.first
count = count.to_i if count
else
0
end
end
# If limit is not set at all, we can ignore offset;
# if limit *is* set but offset is zero, use normal select
# with simple SET ROWCOUNT. Thus, only use the temp table
# if limit is set and offset > 0.
def use_temp_table?
!@limit.nil? && !@offset.nil? && @offset > 0
end
def zero_limit?
!@limit.nil? && @limit == 0
end
def raw_execute(sql, name = nil)
log(sql, name) do
@connection.context.reset
@logger.debug "Setting row count to (#{@limit})" if @logger && @limit
@connection.set_rowcount(@limit || 0)
if sql =~ /^\s*SELECT/i
@connection.sql(sql)
else
@connection.sql_norow(sql)
end
@limit = @offset = nil
if @connection.cmd_fail? or @connection.context.failed?
raise "SQL Command Failed for #{name}: #{sql}\nMessage: #{@connection.context.message}"
end
end
end
# Select limit number of rows starting at optional offset.
def select(sql, name = nil)
if !use_temp_table?
execute(sql, name)
else
log(sql, name) do
# Select into a temp table and prune results
@logger.debug "Selecting #{@limit + (@offset || 0)} or fewer rows into #artemp" if @logger
@connection.context.reset
@connection.set_rowcount(@limit + (@offset || 0))
@connection.sql_norow(sql) # Select into temp table
@logger.debug "Deleting #{@offset || 0} or fewer rows from #artemp" if @logger
@connection.set_rowcount(@offset || 0)
@connection.sql_norow("delete from #artemp") # Delete leading rows
@connection.set_rowcount(0)
@connection.sql("select * from #artemp") # Return the rest
end
end
raise StatementInvalid, "SQL Command Failed for #{name}: #{sql}\nMessage: #{@connection.context.message}" if @connection.context.failed? or @connection.cmd_fail?
rows = []
results = @connection.top_row_result
if results && results.rows.length > 0
fields = results.columns.map { |column| column.sub(/_$/, '') }
results.rows.each do |row|
hashed_row = {}
row.zip(fields) { |cell, column| hashed_row[column] = cell }
rows << hashed_row
end
end
@connection.sql_norow("drop table #artemp") if use_temp_table?
@limit = @offset = nil
rows
end
def get_table_name(sql)
if sql =~ /^\s*insert\s+into\s+([^\(\s]+)\s*|^\s*update\s+([^\(\s]+)\s*/i
$1
elsif sql =~ /from\s+([^\(\s]+)\s*/i
$1
else
nil
end
end
def has_identity_column(table_name)
!get_identity_column(table_name).nil?
end
def get_identity_column(table_name)
@id_columns ||= {}
if !@id_columns.has_key?(table_name)
@logger.debug "Looking up identity column for table '#{table_name}'" if @logger
col = columns(table_name).detect { |col| col.identity }
@id_columns[table_name] = col.nil? ? nil : col.name
end
@id_columns[table_name]
end
def query_contains_identity_column(sql, col)
sql =~ /\[#{col}\]/
end
# Resolve all user-defined types (udt) to their fundamental types.
def resolve_type(field_type)
(@udts ||= {})[field_type] ||= select_one("sp_help #{field_type}")["Storage_type"].strip
end
def normalize_type(field_type, prec, scale, length)
has_scale = (!scale.nil? && scale > 0)
type = if field_type =~ /numeric/i and !has_scale
'int'
elsif field_type =~ /money/i
'numeric'
else
resolve_type(field_type.strip)
end
spec = if prec
has_scale ? "(#{prec},#{scale})" : "(#{prec})"
elsif length && !(type =~ /date|time|text/)
"(#{length})"
else
''
end
"#{type}#{spec}"
end
end # class SybaseAdapter
class SybaseAdapterContext < SybSQLContext
DEADLOCK = 1205
attr_reader :message
def init(logger = nil)
@deadlocked = false
@failed = false
@logger = logger
@message = nil
end
def srvmsgCB(con, msg)
# Do not log change of context messages.
if msg['severity'] == 10 or msg['severity'] == 0
return true
end
if msg['msgnumber'] == DEADLOCK
@deadlocked = true
else
@logger.info "SQL Command failed!" if @logger
@failed = true
end
if @logger
@logger.error "** SybSQLContext Server Message: **"
@logger.error " Message number #{msg['msgnumber']} Severity #{msg['severity']} State #{msg['state']} Line #{msg['line']}"
@logger.error " Server #{msg['srvname']}"
@logger.error " Procedure #{msg['proc']}"
@logger.error " Message String: #{msg['text']}"
end
@message = msg['text']
true
end
def deadlocked?
@deadlocked
end
def failed?
@failed
end
def reset
@deadlocked = false
@failed = false
@message = nil
end
def cltmsgCB(con, msg)
return true unless ( msg.kind_of?(Hash) )
unless ( msg[ "severity" ] ) then
return true
end
if @logger
@logger.error "** SybSQLContext Client-Message: **"
@logger.error " Message number: LAYER=#{msg[ 'layer' ]} ORIGIN=#{msg[ 'origin' ]} SEVERITY=#{msg[ 'severity' ]} NUMBER=#{msg[ 'number' ]}"
@logger.error " Message String: #{msg['msgstring']}"
@logger.error " OS Error: #{msg['osstring']}"
@message = msg['msgstring']
end
@failed = true
# Not retry , CS_CV_RETRY_FAIL( probability TimeOut )
if( msg[ 'severity' ] == "RETRY_FAIL" ) then
@timeout_p = true
return false
end
return true
end
end # class SybaseAdapterContext
end # module ConnectionAdapters
end # module ActiveRecord
# Allow identity inserts for fixtures.
require "active_record/fixtures"
class Fixtures
alias :original_insert_fixtures :insert_fixtures
def insert_fixtures
if @connection.instance_of?(ActiveRecord::ConnectionAdapters::SybaseAdapter)
values.each do |fixture|
@connection.enable_identity_insert(table_name, true)
@connection.execute "INSERT INTO #{@table_name} (#{fixture.key_list}) VALUES (#{fixture.value_list})", 'Fixture Insert'
@connection.enable_identity_insert(table_name, false)
end
else
original_insert_fixtures
end
end
end
rescue LoadError => cannot_require_sybase
# Couldn't load sybase adapter
end