Module: ArJdbc::MSSQL

Includes:
ExplainSupport, LimitHelpers, Utils
Included in:
ActiveRecord::ConnectionAdapters::MSSQLAdapter
Defined in:
lib/arjdbc/mssql/utils.rb,
lib/arjdbc/mssql/column.rb,
lib/arjdbc/mssql/adapter.rb,
lib/arjdbc/mssql/lock_methods.rb,
lib/arjdbc/mssql/limit_helpers.rb,
lib/arjdbc/mssql/explain_support.rb

Defined Under Namespace

Modules: Column, ExplainSupport, LimitHelpers, LockMethods, Utils

Constant Summary collapse

ADAPTER_NAME = 
'MSSQL'.freeze

Constants included from ExplainSupport

ExplainSupport::DISABLED

Constants included from Utils

Utils::GET_TABLE_NAME_FROM_RE, Utils::GET_TABLE_NAME_INSERT_UPDATE_RE

Constants included from LimitHelpers

LimitHelpers::FIND_AGGREGATE_FUNCTIONS

Class Method Summary collapse

Instance Method Summary collapse

Methods included from ExplainSupport

#explain, #set_showplan_option, #supports_explain?, #with_showplan_on

Methods included from Utils

get_table_name, remove_identifier_delimiters, unqualify_db_name, unqualify_table_name, unqualify_table_schema, unquote_column_name, unquote_string, unquote_table_name

Class Method Details

.arel2_visitors(config) ⇒ Object

Deprecated.

no longer used

See Also:

  • ActiveRecord::ConnectionAdapters::JdbcAdapter#arel2_visitors


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# File 'lib/arjdbc/mssql/adapter.rb', line 77

def self.arel2_visitors(config)
  visitor = arel_visitor_type(config)
  { 'mssql' => visitor, 'jdbcmssql' => visitor, 'sqlserver' => visitor }
end

.arel_visitor_type(config) ⇒ Object

See Also:



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# File 'lib/arjdbc/mssql/adapter.rb', line 69

def self.arel_visitor_type(config)
  require 'arel/visitors/sql_server'
  ( config && config[:sqlserver_version].to_s == '2000' ) ?
    ::Arel::Visitors::SQLServer2000 : ::Arel::Visitors::SQLServer
end

.column_selector ⇒ Object

See Also:

  • ActiveRecord::ConnectionAdapters::JdbcColumn#column_types


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# File 'lib/arjdbc/mssql/column.rb', line 5

def self.column_selector
  [ /sqlserver|tds|Microsoft SQL/i, lambda { |config, column| column.extend(Column) } ]
end

.jdbc_connection_class ⇒ Object

See Also:



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# File 'lib/arjdbc/mssql/adapter.rb', line 59

def self.jdbc_connection_class
  ::ActiveRecord::ConnectionAdapters::MSSQLJdbcConnection
end

.update_lob_values=(update) ⇒ Object

See Also:

  • #update_lob_values?


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# File 'lib/arjdbc/mssql/adapter.rb', line 46

def self.update_lob_values=(update); @@update_lob_values = update; end

.update_lob_values? ⇒ Boolean

Note:

This only applies when prepared statements are not used.

Updating records with LOB values (binary/text columns) in a separate statement can be disabled using :

ArJdbc::MSSQL.update_lob_values = false

Returns:

  • (Boolean) 


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# File 'lib/arjdbc/mssql/adapter.rb', line 44

def self.update_lob_values?; @@update_lob_values; end

Instance Method Details

#adapter_name ⇒ Object 



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# File 'lib/arjdbc/mssql/adapter.rb', line 230

def adapter_name
  ADAPTER_NAME
end

#add_column(table_name, column_name, type, options = {}) ⇒ Object

Adds a new column to the named table.



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# File 'lib/arjdbc/mssql/adapter.rb', line 348

def add_column(table_name, column_name, type, options = {})
  clear_cached_table(table_name)
  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)
  # TODO: Add support to mimic date columns, using constraints to mark them as such in the database
  # add_column_sql << " CONSTRAINT ck__#{table_name}__#{column_name}__date_only CHECK ( CONVERT(CHAR(12), #{quote_column_name(column_name)}, 14)='00:00:00:000' )" if type == :date
  execute(add_column_sql)
end

#change_column(table_name, column_name, type, options = {}) ⇒ Object 



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# File 'lib/arjdbc/mssql/adapter.rb', line 390

def change_column(table_name, column_name, type, options = {})

  indexes = []
  column_object = columns(table_name).detect { |c| c.name.to_s == column_name.to_s }

  if options_include_default?(options) || (column_object && column_object.type != type.to_sym)
    remove_default_constraint(table_name, column_name)
    indexes = indexes(table_name).select{ |index| index.columns.include?(column_name.to_s) }
    remove_indexes(table_name, column_name)
  end

  clear_cached_table(table_name)
  change_column_type(table_name, column_name, type, options)
  change_column_default(table_name, column_name, options[:default]) if options_include_default?(options)

  #Add any removed indexes back
  indexes.each do |index|
    execute "CREATE INDEX #{quote_table_name(index.name)} ON #{quote_table_name(table_name)} (#{index.columns.collect {|c|quote_column_name(c)}.join(', ')})"
  end
end

#change_column_default(table_name, column_name, default) ⇒ Object 



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# File 'lib/arjdbc/mssql/adapter.rb', line 418

def change_column_default(table_name, column_name, default)
  clear_cached_table(table_name)
  remove_default_constraint(table_name, column_name)
  unless default.nil?
    execute "ALTER TABLE #{quote_table_name(table_name)} ADD CONSTRAINT DF_#{table_name}_#{column_name} DEFAULT #{quote(default)} FOR #{quote_column_name(column_name)}"
  end
end

#change_column_type(table_name, column_name, type, options = {}) ⇒ Object 



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# File 'lib/arjdbc/mssql/adapter.rb', line 411

def change_column_type(table_name, column_name, type, options = {})
  clear_cached_table(table_name)
  sql = "ALTER TABLE #{quote_table_name(table_name)} ALTER COLUMN #{quote_column_name(column_name)} #{type_to_sql(type, options[:limit], options[:precision], options[:scale])}"
  sql += (options[:null] ? " NULL" : " NOT NULL") if options.has_key?(:null)
  execute(sql)
end

#change_order_direction(order) ⇒ Object 



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# File 'lib/arjdbc/mssql/adapter.rb', line 234

def change_order_direction(order)
  asc, desc = /\bASC\b/i, /\bDESC\b/i
  order.split(",").collect do |fragment|
    case fragment
    when desc  then fragment.gsub(desc, "ASC")
    when asc   then fragment.gsub(asc, "DESC")
    else "#{fragment.split(',').join(' DESC,')} DESC"
    end
  end.join(",")
end

#charset ⇒ Object 



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# File 'lib/arjdbc/mssql/adapter.rb', line 292

def charset
  select_value "SELECT SERVERPROPERTY('SqlCharSetName')"
end

#clear_cached_table(table_name) ⇒ Object 



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# File 'lib/arjdbc/mssql/adapter.rb', line 533

def clear_cached_table(table_name)
  ( @table_columns ||= {} ).delete(table_name.to_s)
end

#collation ⇒ Object 



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# File 'lib/arjdbc/mssql/adapter.rb', line 296

def collation
  select_value "SELECT SERVERPROPERTY('Collation')"
end

#columns(table_name, name = nil, default = EMPTY_ARRAY) ⇒ Object 



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# File 'lib/arjdbc/mssql/adapter.rb', line 512

def columns(table_name, name = nil, default = EMPTY_ARRAY)
  # It's possible for table_name to be an empty string, or nil, if something
  # attempts to issue SQL which doesn't involve a table.
  # IE. "SELECT 1" or "SELECT * FROM someFunction()".
  return default if table_name.blank?

  table_name = unquote_table_name(table_name)

  return default if table_name =~ SKIP_COLUMNS_TABLE_NAMES_RE

  unless columns = ( @table_columns ||= {} )[table_name]
    columns = super(table_name, name)
    for column in columns
      column.identity = true if column.sql_type =~ IDENTITY_COLUMN_TYPE_RE
      column.special = true if column.sql_type =~ SPECIAL_COLUMN_TYPE_RE
    end
    @table_columns[table_name] = columns
  end
  columns
end

#columns_for_distinct(columns, orders) ⇒ Object 



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# File 'lib/arjdbc/mssql/adapter.rb', line 369

def columns_for_distinct(columns, orders)
  return columns if orders.blank?

  # construct a clean list of column names from the ORDER BY clause,
  # removing any ASC/DESC modifiers
  order_columns = [ orders ]; order_columns.flatten! # AR 3.x vs 4.x
  order_columns.map! do |column|
    column = column.to_sql unless column.is_a?(String) # handle AREL node
    column.split(',').collect!{ |s| s.split.first }
  end.flatten!
  order_columns.reject!(&:blank?)
  order_columns = order_columns.zip(0...order_columns.size).to_a
  order_columns = order_columns.map{ |s, i| "#{s}" }

  columns = [ columns ]; columns.flatten!
  columns.push( *order_columns ).join(', ')
  # return a DISTINCT clause that's distinct on the columns we want but
  # includes all the required columns for the ORDER BY to work properly
end

#configure_connection ⇒ Object 



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# File 'lib/arjdbc/mssql/adapter.rb', line 82

def configure_connection
  use_database # config[:database]
end

#create_database(name, options = {}) ⇒ Object 



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# File 'lib/arjdbc/mssql/adapter.rb', line 332

def create_database(name, options = {})
  execute "CREATE DATABASE #{quote_table_name(name)}"
end

#current_database ⇒ Object 



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# File 'lib/arjdbc/mssql/adapter.rb', line 300

def current_database
  select_value 'SELECT DB_NAME()'
end

#current_user ⇒ Object

SELECT CURRENT_USER



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# File 'lib/arjdbc/mssql/adapter.rb', line 288

def current_user
  @current_user ||= @connection.execute_query_raw("SELECT CURRENT_USER").first['']
end

#database_exists?(name) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/arjdbc/mssql/adapter.rb', line 336

def database_exists?(name)
  select_value "SELECT name FROM sys.databases WHERE name = '#{name}'"
end

#default_schema ⇒ Object Also known as: current_schema

Returns the default schema (to be used for table resolution) used for the #current_user.



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# File 'lib/arjdbc/mssql/adapter.rb', line 268

def default_schema
  return current_user if sqlserver_2000?
  @default_schema ||=
    @connection.execute_query_raw(
      "SELECT default_schema_name FROM sys.database_principals WHERE name = CURRENT_USER"
    ).first['default_schema_name']
end

#default_schema=(default_schema) ⇒ Object Also known as: current_schema=

Note:

This is not supported on SQL Server 2000 !

Allows for changing of the default schema (to be used during unqualified table name resolution).



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# File 'lib/arjdbc/mssql/adapter.rb', line 280

def default_schema=(default_schema) # :nodoc:
  raise "changing DEFAULT_SCHEMA only supported on SQLServer 2005+" if sqlserver_2000?
  execute("ALTER #{current_user} WITH DEFAULT_SCHEMA=#{default_schema}")
  @default_schema = nil if defined?(@default_schema)
end

#distinct(columns, order_by) ⇒ Object

SELECT DISTINCT clause for a given set of columns and a given ORDER BY clause. MSSQL requires the ORDER BY columns in the select list for distinct queries.



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# File 'lib/arjdbc/mssql/adapter.rb', line 365

def distinct(columns, order_by)
  "DISTINCT #{columns_for_distinct(columns, order_by)}"
end

#drop_database(name) ⇒ Object 



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# File 'lib/arjdbc/mssql/adapter.rb', line 326

def drop_database(name)
  current_db = current_database
  use_database('master') if current_db.to_s == name
  execute "DROP DATABASE #{quote_table_name(name)}"
end

#exec_proc(proc_name, *variables) ⇒ Object Also known as: execute_procedure

Support for executing a stored procedure.



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# File 'lib/arjdbc/mssql/adapter.rb', line 576

def exec_proc(proc_name, *variables)
  vars =
    if variables.any? && variables.first.is_a?(Hash)
      variables.first.map { |k, v| "@#{k} = #{quote(v)}" }
    else
      variables.map { |v| quote(v) }
    end.join(', ')
  sql = "EXEC #{proc_name} #{vars}".strip
  log(sql, 'Execute Procedure') do
    result = @connection.execute_query_raw(sql)
    result.map! do |row|
      row = row.is_a?(Hash) ? row.with_indifferent_access : row
      yield(row) if block_given?
      row
    end
    result
  end
end

#exec_query(sql, name = 'SQL', binds = []) ⇒ Object 



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# File 'lib/arjdbc/mssql/adapter.rb', line 597

def exec_query(sql, name = 'SQL', binds = [])
  # NOTE: we allow to execute SQL as requested returning a results.
  # e.g. this allows to use SQLServer's EXEC with a result set ...
  if sql.respond_to?(:to_sql)
    sql = to_sql(sql, binds); to_sql = true
  end
  sql = repair_special_columns(sql)
  if prepared_statements?
    log(sql, name, binds) { @connection.execute_query(sql, binds) }
  else
    sql = suble_binds(sql, binds) unless to_sql # deprecated behavior
    log(sql, name) { @connection.execute_query(sql) }
  end
end

#exec_query_raw(sql, name = 'SQL', binds = [], &block) ⇒ Object 



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# File 'lib/arjdbc/mssql/adapter.rb', line 613

def exec_query_raw(sql, name = 'SQL', binds = [], &block)
  if sql.respond_to?(:to_sql)
    sql = to_sql(sql, binds); to_sql = true
  end
  sql = repair_special_columns(sql)
  if prepared_statements?
    log(sql, name, binds) { @connection.execute_query_raw(sql, binds, &block) }
  else
    sql = suble_binds(sql, binds) unless to_sql # deprecated behavior
    log(sql, name) { @connection.execute_query_raw(sql, &block) }
  end
end

#jdbc_column_class ⇒ Object

See Also:



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# File 'lib/arjdbc/mssql/adapter.rb', line 64

def jdbc_column_class
  ::ActiveRecord::ConnectionAdapters::MSSQLColumn
end

#modify_types(types) ⇒ Object 



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# File 'lib/arjdbc/mssql/adapter.rb', line 94

def modify_types(types)
  types[:string] = { :name => "NVARCHAR", :limit => 255 }
  if sqlserver_2000?
    types[:text] = { :name => "NTEXT" }
  else
    types[:text] = { :name => "NVARCHAR(MAX)" }
  end
  types[:primary_key] = "int NOT NULL IDENTITY(1, 1) PRIMARY KEY"
  types[:integer][:limit] = nil
  types[:boolean] = { :name => "bit" }
  types[:binary] = { :name => "image" }
  types
end

#quote(value, column = nil) ⇒ Object 



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# File 'lib/arjdbc/mssql/adapter.rb', line 144

def quote(value, column = nil)
  return value.quoted_id if value.respond_to?(:quoted_id)
  return value if sql_literal?(value)

  case value
  # SQL Server 2000 doesn't let you insert an integer into a NVARCHAR
  when String, ActiveSupport::Multibyte::Chars, Integer
    value = value.to_s
    column_type = column && column.type
    if column_type == :binary
      if update_lob_value?(value, column)
        BLOB_VALUE_MARKER
      else
        "'#{quote_string(column.class.string_to_binary(value))}'" # ' (for ruby-mode)
      end
    elsif column_type == :integer
      value.to_i.to_s
    elsif column_type == :float
      value.to_f.to_s
    elsif ! column.respond_to?(:is_utf8?) || column.is_utf8?
      "N'#{quote_string(value)}'" # ' (for ruby-mode)
    else
      super
    end
  when Date, Time
    if column && column.type == :time
      "'#{quoted_time(value)}'"
    else
      "'#{quoted_date(value)}'"
    end
  when TrueClass  then '1'
  when FalseClass then '0'
  else super
  end
end

#quote_column_name(name) ⇒ Object 



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# File 'lib/arjdbc/mssql/adapter.rb', line 222

def quote_column_name(name)
  name.to_s.split('.').map do |n| # "[#{name}]"
    n =~ /^\[.*\]$/ ? n : "[#{n.gsub(']', ']]')}]"
  end.join('.')
end

#quote_table_name(name) ⇒ Object 



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# File 'lib/arjdbc/mssql/adapter.rb', line 218

def quote_table_name(name)
  quote_column_name(name)
end

#quoted_date(value) ⇒ Object 



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# File 'lib/arjdbc/mssql/adapter.rb', line 181

def quoted_date(value)
  if value.respond_to?(:usec)
    "#{super}.#{sprintf("%03d", value.usec / 1000)}"
  else
    super
  end
end

#release_savepoint(name = current_savepoint_name) ⇒ Object 



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# File 'lib/arjdbc/mssql/adapter.rb', line 627

def release_savepoint(name = current_savepoint_name)
  if @connection.jtds_driver?
    @connection.release_savepoint(name)
  else # MS invented it's "own" way
    @connection.rollback_savepoint(name)
  end
end

#remove_check_constraints(table_name, column_name) ⇒ Object 



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# File 'lib/arjdbc/mssql/adapter.rb', line 478

def remove_check_constraints(table_name, column_name)
  clear_cached_table(table_name)
  constraints = select_values "SELECT constraint_name" <<
    " FROM information_schema.constraint_column_usage" <<
    " WHERE table_name = '#{table_name}' AND column_name = '#{column_name}'"
  constraints.each do |constraint_name|
    execute "ALTER TABLE #{table_name} DROP CONSTRAINT #{constraint_name}"
  end
end

#remove_column(table_name, *column_names) ⇒ Object 



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# File 'lib/arjdbc/mssql/adapter.rb', line 448

def remove_column(table_name, column_name, type = nil, options = {})
  remove_columns(table_name, column_name)
end

#remove_columns(table_name, *column_names) ⇒ Object

Raises:

  • (ArgumentError) 


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# File 'lib/arjdbc/mssql/adapter.rb', line 426

def remove_columns(table_name, *column_names)
  raise ArgumentError.new("You must specify at least one column name. Example: remove_column(:people, :first_name)") if column_names.empty?
  # remove_columns(:posts, :foo, :bar) old syntax : remove_columns(:posts, [:foo, :bar])
  clear_cached_table(table_name)

  return do_remove_column(table_name, column_names.first) if column_names.size == 1
  column_names.flatten.each do |column_name|
    do_remove_column(table_name, column_name)
  end
end

#remove_default_constraint(table_name, column_name) ⇒ Object 



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# File 'lib/arjdbc/mssql/adapter.rb', line 458

def remove_default_constraint(table_name, column_name)
  clear_cached_table(table_name)
  if sqlserver_2000?
    # NOTE: since SQLServer 2005 these are provided as sys.sysobjects etc.
    # but only due backwards-compatibility views and should be avoided ...
    defaults = select_values "SELECT d.name" <<
      " FROM sysobjects d, syscolumns c, sysobjects t" <<
      " WHERE c.cdefault = d.id AND c.name = '#{column_name}'" <<
      " AND t.name = '#{table_name}' AND c.id = t.id"
  else
    defaults = select_values "SELECT d.name FROM sys.tables t" <<
      " JOIN sys.default_constraints d ON d.parent_object_id = t.object_id" <<
      " JOIN sys.columns c ON c.object_id = t.object_id AND c.column_id = d.parent_column_id" <<
      " WHERE t.name = '#{table_name}' AND c.name = '#{column_name}'"
  end
  defaults.each do |def_name|
    execute "ALTER TABLE #{table_name} DROP CONSTRAINT #{def_name}"
  end
end

#remove_index(table_name, options = {}) ⇒ Object 



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# File 'lib/arjdbc/mssql/adapter.rb', line 495

def remove_index(table_name, options = {})
  execute "DROP INDEX #{quote_table_name(table_name)}.#{index_name(table_name, options)}"
end

#remove_indexes(table_name, column_name) ⇒ Object 



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# File 'lib/arjdbc/mssql/adapter.rb', line 488

def remove_indexes(table_name, column_name)
  indexes = self.indexes(table_name)
  indexes.select{ |index| index.columns.include?(column_name.to_s) }.each do |index|
    remove_index(table_name, { :name => index.name })
  end
end

#rename_column(table_name, column_name, new_column_name) ⇒ Object 



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# File 'lib/arjdbc/mssql/adapter.rb', line 358

def rename_column(table_name, column_name, new_column_name)
  clear_cached_table(table_name)
  execute "EXEC sp_rename '#{table_name}.#{column_name}', '#{new_column_name}', 'COLUMN'"
end

#rename_table(table_name, new_table_name) ⇒ Object 



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# File 'lib/arjdbc/mssql/adapter.rb', line 341

def rename_table(table_name, new_table_name)
  clear_cached_table(table_name)
  execute "EXEC sp_rename '#{table_name}', '#{new_table_name}'"
end

#reset_column_information ⇒ Object 



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# File 'lib/arjdbc/mssql/adapter.rb', line 537

def reset_column_information
  @table_columns = nil if defined? @table_columns
end

#set_identity_insert(table_name, enable = true) ⇒ Object 



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# File 'lib/arjdbc/mssql/adapter.rb', line 551

def set_identity_insert(table_name, enable = true)
  execute "SET IDENTITY_INSERT #{table_name} #{enable ? 'ON' : 'OFF'}"
rescue Exception => e
  raise ActiveRecord::ActiveRecordError, "IDENTITY_INSERT could not be turned" +
        " #{enable ? 'ON' : 'OFF'} for table #{table_name} due : #{e.inspect}"
end

#sqlserver_version ⇒ Object 



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# File 'lib/arjdbc/mssql/adapter.rb', line 86

def sqlserver_version
  @sqlserver_version ||= begin
    config_version = config[:sqlserver_version]
    config_version ? config_version.to_s :
      select_value("SELECT @@version")[/(Microsoft SQL Server\s+|Microsoft SQL Azure.+\n.+)(\d{4})/, 2]
  end
end

#supports_ddl_transactions? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/arjdbc/mssql/adapter.rb', line 245

def supports_ddl_transactions?
  true
end

#tables(schema = current_schema) ⇒ Object 



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# File 'lib/arjdbc/mssql/adapter.rb', line 249

def tables(schema = current_schema)
  @connection.tables(nil, schema)
end

#type_to_sql(type, limit = nil, precision = nil, scale = nil) ⇒ Object 



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# File 'lib/arjdbc/mssql/adapter.rb', line 111

def type_to_sql(type, limit = nil, precision = nil, scale = nil)
  type_s = type.to_s
  # MSSQL's NVARCHAR(n | max) column supports either a number between 1 and
  # 4000, or the word "MAX", which corresponds to 2**30-1 UCS-2 characters.
  #
  # It does not accept NVARCHAR(1073741823) here, so we have to change it
  # to NVARCHAR(MAX), even though they are logically equivalent.
  #
  # MSSQL Server 2000 is skipped here because I don't know how it will behave.
  #
  # See: http://msdn.microsoft.com/en-us/library/ms186939.aspx
  if type_s == 'string' && limit == 1073741823 && ! sqlserver_2000?
    'NVARCHAR(MAX)'
  elsif NO_LIMIT_TYPES.include?(type_s)
    super(type)
  elsif type_s == 'integer' || type_s == 'int'
    if limit.nil? || limit == 4
      'int'
    elsif limit == 2
      'smallint'
    elsif limit == 1
      'tinyint'
    else
      'bigint'
    end
  elsif type_s == 'uniqueidentifier'
    type_s
  else
    super
  end
end

#update_lob_value?(value, column = nil) ⇒ Boolean

Returns:

  • (Boolean)

See Also:



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# File 'lib/arjdbc/mssql/adapter.rb', line 54

def update_lob_value?(value, column = nil)
  MSSQL.update_lob_values? && ! prepared_statements? # && value
end

#use_database(database = nil) ⇒ Object 



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# File 'lib/arjdbc/mssql/adapter.rb', line 304

def use_database(database = nil)
  database ||= config[:database]
  execute "USE #{quote_table_name(database)}" unless database.blank?
end

#with_identity_insert_enabled(table_name) ⇒ Object

Turns IDENTITY_INSERT ON for table during execution of the block N.B. This sets the state of IDENTITY_INSERT to OFF after the block has been executed without regard to its previous state



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# File 'lib/arjdbc/mssql/adapter.rb', line 544

def with_identity_insert_enabled(table_name)
  set_identity_insert(table_name, true)
  yield
ensure
  set_identity_insert(table_name, false)
end