Module: ArJdbc::MySQL

Includes:
BulkChangeTable
Included in:
ActiveRecord::ConnectionAdapters::MysqlAdapter
Defined in:
lib/arjdbc/mysql/column.rb,
lib/arjdbc/mysql/adapter.rb,
lib/arjdbc/mysql/explain_support.rb,
lib/arjdbc/mysql/schema_creation.rb,
lib/arjdbc/mysql/bulk_change_table.rb

Defined Under Namespace

Modules: BulkChangeTable, Column, ExplainSupport Classes: SchemaCreation

Constant Summary collapse

NATIVE_DATABASE_TYPES = 
{
  :primary_key => "int(11) auto_increment PRIMARY KEY",
  :string => { :name => "varchar", :limit => 255 },
  :text => { :name => "text" },
  :integer => { :name => "int", :limit => 4 },
  :float => { :name => "float" },
  # :double => { :name=>"double", :limit=>17 }
  # :real => { :name=>"real", :limit=>17 }
  :numeric => { :name => "numeric" }, # :limit => 65
  :decimal => { :name => "decimal" }, # :limit => 65
  :datetime => { :name => "datetime" },
  # TIMESTAMP has varying properties depending on MySQL version (SQL mode)
  :timestamp => { :name => "datetime" },
  :time => { :name => "time" },
  :date => { :name => "date" },
  :binary => { :name => "blob" },
  :boolean => { :name => "tinyint", :limit => 1 },
  # AR-JDBC added :
  :bit => { :name => "bit" }, # :limit => 1
  :enum => { :name => "enum" },
  :set => { :name => "set" }, # :limit => 64
  :char => { :name => "char" }, # :limit => 255
}
ADAPTER_NAME = 
'MySQL'.freeze
INDEX_TYPES = 
[ :fulltext, :spatial ]
INDEX_USINGS = 
[ :btree, :hash ]

Class Method Summary collapse

Instance Method Summary collapse

Methods included from BulkChangeTable

#add_column_sql, #add_index_sql, #add_timestamps_sql, #bulk_change_table, #change_column_sql, #remove_column_sql, #remove_columns_sql, #remove_index_sql, #remove_timestamps_sql, #rename_column_sql, #supports_bulk_alter?

Class Method Details

.arel_visitor_type(config = nil) ⇒ Object 



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# File 'lib/arjdbc/mysql/adapter.rb', line 140

def self.arel_visitor_type(config = nil)
  ::Arel::Visitors::MySQL
end

.column_selector ⇒ Object

See Also:

  • ActiveRecord::ConnectionAdapters::JdbcColumn#column_types


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

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

.emulate_booleans ⇒ Object

Deprecated.

Use #emulate_booleans? instead.



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# File 'lib/arjdbc/mysql/adapter.rb', line 100

def self.emulate_booleans; @@emulate_booleans; end

.emulate_booleans=(emulate) ⇒ Object

See Also:

  • #emulate_booleans?


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# File 'lib/arjdbc/mysql/adapter.rb', line 102

def self.emulate_booleans=(emulate); @@emulate_booleans = emulate; end

.emulate_booleans? ⇒ Boolean

Boolean emulation can be disabled using (or using the adapter method) :

ArJdbc::MySQL.emulate_booleans = false

Returns:

  • (Boolean)

See Also:

  • ActiveRecord::ConnectionAdapters::MysqlAdapter#emulate_booleans


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# File 'lib/arjdbc/mysql/adapter.rb', line 98

def self.emulate_booleans?; @@emulate_booleans; end

.jdbc_connection_class ⇒ Object

See Also:



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# File 'lib/arjdbc/mysql/adapter.rb', line 20

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

Instance Method Details

#adapter_name ⇒ Object 



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# File 'lib/arjdbc/mysql/adapter.rb', line 136

def adapter_name
  ADAPTER_NAME
end

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



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# File 'lib/arjdbc/mysql/adapter.rb', line 598

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)
  add_column_position!(add_column_sql, options)
  execute(add_column_sql)
end

#add_column_position!(sql, options) ⇒ Object 



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# File 'lib/arjdbc/mysql/adapter.rb', line 664

def add_column_position!(sql, options)
  if options[:first]
    sql << " FIRST"
  elsif options[:after]
    sql << " AFTER #{quote_column_name(options[:after])}"
  end
end

#add_limit_offset!(sql, options) ⇒ Object

Note:

Only used with (non-AREL) ActiveRecord 2.3.

See Also:

  • Arel::Visitors::MySQL


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# File 'lib/arjdbc/mysql/adapter.rb', line 674

def add_limit_offset!(sql, options)
  limit, offset = options[:limit], options[:offset]
  if limit && offset
    sql << " LIMIT #{offset.to_i}, #{sanitize_limit(limit)}"
  elsif limit
    sql << " LIMIT #{sanitize_limit(limit)}"
  elsif offset
    sql << " OFFSET #{offset.to_i}"
  end
  sql
end

#case_insensitive_comparison(table, attribute, column, value) ⇒ Object 



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# File 'lib/arjdbc/mysql/adapter.rb', line 171

def case_insensitive_comparison(table, attribute, column, value)
  if column.case_sensitive?
    super
  else
    table[attribute].eq(value)
  end
end

#case_sensitive_comparison(table, attribute, column, value) ⇒ Object 



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# File 'lib/arjdbc/mysql/adapter.rb', line 163

def case_sensitive_comparison(table, attribute, column, value)
  if column.case_sensitive?
    table[attribute].eq(value)
  else
    super
  end
end

#case_sensitive_equality_operator ⇒ Object 



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# File 'lib/arjdbc/mysql/adapter.rb', line 150

def case_sensitive_equality_operator
  "= BINARY"
end

#case_sensitive_modifier(node, table_attribute) ⇒ Object 



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# File 'lib/arjdbc/mysql/adapter.rb', line 154

def case_sensitive_modifier(node)
  Arel::Nodes::Bin.new(node)
end

#change_column_default(table_name, column_name, default) ⇒ Object 



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# File 'lib/arjdbc/mysql/adapter.rb', line 605

def change_column_default(table_name, column_name, default)
  column = column_for(table_name, column_name)
  change_column table_name, column_name, column.sql_type, :default => default
end

#change_column_null(table_name, column_name, null, default = nil) ⇒ Object

unless const_defined? :SchemaCreation



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# File 'lib/arjdbc/mysql/adapter.rb', line 610

def change_column_null(table_name, column_name, null, default = nil)
  column = column_for(table_name, column_name)

  unless null || default.nil?
    execute("UPDATE #{quote_table_name(table_name)} SET #{quote_column_name(column_name)}=#{quote(default)} WHERE #{quote_column_name(column_name)} IS NULL")
  end

  change_column table_name, column_name, column.sql_type, :null => null
end

#charset ⇒ Object 



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# File 'lib/arjdbc/mysql/adapter.rb', line 714

def charset
  show_variable("character_set_database")
end

#clear_cache! ⇒ Object 



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# File 'lib/arjdbc/mysql/adapter.rb', line 771

def clear_cache!
  super
  reload_type_map
end

#collation ⇒ Object 



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# File 'lib/arjdbc/mysql/adapter.rb', line 718

def collation
  show_variable("collation_database")
end

#columns(table_name, name = nil) ⇒ Object

Returns an array of Column objects for the table specified.



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# File 'lib/arjdbc/mysql/adapter.rb', line 409

def columns(table_name, name = nil)
  sql = "SHOW FULL #{AR40 ? 'FIELDS' : 'COLUMNS'} FROM #{quote_table_name(table_name)}"
  columns = execute(sql, name || 'SCHEMA')
  strict = strict_mode?
  pass_cast_type = respond_to?(:lookup_cast_type)
  columns.map! do |field|
    sql_type = field['Type']
    null = field['Null'] == "YES"
    if pass_cast_type
      cast_type = lookup_cast_type(sql_type)
      jdbc_column_class.new(field['Field'], field['Default'], cast_type, sql_type, null, field['Collation'], strict, field['Extra'])
    else
      jdbc_column_class.new(field['Field'], field['Default'], sql_type, null, field['Collation'], strict, field['Extra'])
    end
  end
  columns
end

#configure_connection ⇒ Object 



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

def configure_connection
  variables = config[:variables] || {}
  # By default, MySQL 'where id is null' selects the last inserted id. Turn this off.
  variables[:sql_auto_is_null] = 0 # execute "SET SQL_AUTO_IS_NULL=0"

  # Increase timeout so the server doesn't disconnect us.
  wait_timeout = config[:wait_timeout]
  wait_timeout = self.class.type_cast_config_to_integer(wait_timeout)
  variables[:wait_timeout] = wait_timeout.is_a?(Integer) ? wait_timeout : 2147483

  # Make MySQL reject illegal values rather than truncating or blanking them, see
  # http://dev.mysql.com/doc/refman/5.0/en/server-sql-mode.html#sqlmode_strict_all_tables
  # If the user has provided another value for sql_mode, don't replace it.
  if strict_mode? && ! variables.has_key?(:sql_mode)
    variables[:sql_mode] = 'STRICT_ALL_TABLES' # SET SQL_MODE='STRICT_ALL_TABLES'
  end
  
  # NAMES does not have an equals sign, see
  # http://dev.mysql.com/doc/refman/5.0/en/set-statement.html#id944430
  # (trailing comma because variable_assignments will always have content)
  if @config[:encoding]
    encoding = "NAMES #{@config[:encoding]}"
    encoding << " COLLATE #{@config[:collation]}" if @config[:collation]
    encoding << ", "
  end

  # Gather up all of the SET variables...
  variable_assignments = variables.map do |k, v|
    if v == ':default' || v == :default
      "@@SESSION.#{k.to_s} = DEFAULT" # Sets the value to the global or compile default
    elsif ! v.nil?
      "@@SESSION.#{k.to_s} = #{quote(v)}"
    end
    # or else nil; compact to clear nils out
  end.compact.join(', ')

  # ...and send them all in one query
  execute("SET #{encoding} #{variable_assignments}", :skip_logging)
end

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



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# File 'lib/arjdbc/mysql/adapter.rb', line 505

def create_database(name, options = {})
  if options[:collation]
    execute "CREATE DATABASE `#{name}` DEFAULT CHARACTER SET `#{options[:charset] || 'utf8'}` COLLATE `#{options[:collation]}`"
  else
    execute "CREATE DATABASE `#{name}` DEFAULT CHARACTER SET `#{options[:charset] || 'utf8'}`"
  end
end

#create_savepoint(name = current_savepoint_name(true)) ⇒ Object 



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# File 'lib/arjdbc/mysql/adapter.rb', line 301

def create_savepoint(name = current_savepoint_name(true))
  log("SAVEPOINT #{name}", 'Savepoint') { super }
end

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



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# File 'lib/arjdbc/mysql/adapter.rb', line 527

def create_table(name, options = {})
  super(name, { :options => "ENGINE=InnoDB" }.merge(options))
end

#current_database ⇒ Object 



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# File 'lib/arjdbc/mysql/adapter.rb', line 518

def current_database
  select_one("SELECT DATABASE() as db")['db']
end

#disable_referential_integrity ⇒ Object 



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# File 'lib/arjdbc/mysql/adapter.rb', line 315

def disable_referential_integrity
  fk_checks = select_value("SELECT @@FOREIGN_KEY_CHECKS")
  begin
    update("SET FOREIGN_KEY_CHECKS = 0")
    yield
  ensure
    update("SET FOREIGN_KEY_CHECKS = #{fk_checks}")
  end
end

#drop_database(name) ⇒ Object 



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# File 'lib/arjdbc/mysql/adapter.rb', line 514

def drop_database(name)
  execute "DROP DATABASE IF EXISTS `#{name}`"
end

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



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# File 'lib/arjdbc/mysql/adapter.rb', line 531

def drop_table(table_name, options = {})
  execute "DROP#{' TEMPORARY' if options[:temporary]} TABLE #{quote_table_name(table_name)}"
end

#empty_insert_statement_value ⇒ Object 



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# File 'lib/arjdbc/mysql/adapter.rb', line 762

def empty_insert_statement_value
  "VALUES ()"
end

#foreign_keys(table_name) ⇒ Object 



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# File 'lib/arjdbc/mysql/adapter.rb', line 563

def foreign_keys(table_name)
  fk_info = select_all "" <<
    "SELECT fk.referenced_table_name as 'to_table' " <<
          ",fk.referenced_column_name as 'primary_key' " <<
          ",fk.column_name as 'column' " <<
          ",fk.constraint_name as 'name' " <<
    "FROM information_schema.key_column_usage fk " <<
    "WHERE fk.referenced_column_name is not null " <<
      "AND fk.table_schema = '#{current_database}' " <<
      "AND fk.table_name = '#{table_name}'"

  create_table_info = select_one("SHOW CREATE TABLE #{quote_table_name(table_name)}")["Create Table"]

  fk_info.map! do |row|
    options = {
      :column => row['column'], :name => row['name'], :primary_key => row['primary_key']
    }
    options[:on_update] = extract_foreign_key_action(create_table_info, row['name'], "UPDATE")
    options[:on_delete] = extract_foreign_key_action(create_table_info, row['name'], "DELETE")

    ForeignKeyDefinition.new(table_name, row['to_table'], options)
  end
end

#index_algorithms ⇒ Object 



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# File 'lib/arjdbc/mysql/adapter.rb', line 284

def index_algorithms
  { :default => 'ALGORITHM = DEFAULT', :copy => 'ALGORITHM = COPY', :inplace => 'ALGORITHM = INPLACE' }
end

#indexes(table_name, name = nil) ⇒ Object

Returns an array of indexes for the given table.



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# File 'lib/arjdbc/mysql/adapter.rb', line 381

def indexes(table_name, name = nil)
  indexes = []
  current_index = nil
  result = execute("SHOW KEYS FROM #{quote_table_name(table_name)}", name || 'SCHEMA')
  result.each do |row|
    key_name = row['Key_name']
    if current_index != key_name
      next if key_name == 'PRIMARY' # skip the primary key
      current_index = key_name
      indexes <<
        if self.class.const_defined?(:INDEX_TYPES) # AR 4.0
          mysql_index_type = row['Index_type'].downcase.to_sym
          index_type = INDEX_TYPES.include?(mysql_index_type) ? mysql_index_type : nil
          index_using = INDEX_USINGS.include?(mysql_index_type) ? mysql_index_type : nil
          IndexDefinition.new(row['Table'], key_name, row['Non_unique'].to_i == 0, [], [], nil, nil, index_type, index_using)
        else
          IndexDefinition.new(row['Table'], key_name, row['Non_unique'].to_i == 0, [], [])
        end
    end

    indexes.last.columns << row["Column_name"]
    indexes.last.lengths << row["Sub_part"]
  end
  indexes
end

#initialize_schema_migrations_table ⇒ Object 



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# File 'lib/arjdbc/mysql/adapter.rb', line 183

def initialize_schema_migrations_table
  if @config[:encoding] == 'utf8mb4'
    ActiveRecord::SchemaMigration.create_table(191)
  else
    ActiveRecord::SchemaMigration.create_table
  end
end

#jdbc_column_class ⇒ Object 



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# File 'lib/arjdbc/mysql/adapter.rb', line 24

def jdbc_column_class
  ::ActiveRecord::ConnectionAdapters::MysqlAdapter::Column
end

#limited_update_conditions(where_sql, quoted_table_name, quoted_primary_key) ⇒ Object 



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# File 'lib/arjdbc/mysql/adapter.rb', line 179

def limited_update_conditions(where_sql, quoted_table_name, quoted_primary_key)
  where_sql
end

#native_database_types ⇒ Object 



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# File 'lib/arjdbc/mysql/adapter.rb', line 129

def native_database_types
  NATIVE_DATABASE_TYPES
end

#pk_and_sequence_for(table) ⇒ Object

Note:

Not used, only here for potential compatibility with native adapter.

Returns a table's primary key and belonging sequence.



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# File 'lib/arjdbc/mysql/adapter.rb', line 363

def pk_and_sequence_for(table)
  result = execute("SHOW CREATE TABLE #{quote_table_name(table)}", 'SCHEMA').first
  if result['Create Table'].to_s =~ /PRIMARY KEY\s+(?:USING\s+\w+\s+)?\((.+)\)/
    keys = $1.split(","); keys.map! { |key| key.gsub(/[`"]/, "") }
    return keys.length == 1 ? [ keys.first, nil ] : nil
  else
    return nil
  end
end

#primary_key(table) ⇒ Object

Returns just a table's primary key.



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# File 'lib/arjdbc/mysql/adapter.rb', line 354

def primary_key(table)
  #pk_and_sequence = pk_and_sequence_for(table)
  #pk_and_sequence && pk_and_sequence.first
  @connection.primary_keys(table).first
end

#quote_column_name(name) ⇒ Object 



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# File 'lib/arjdbc/mysql/adapter.rb', line 235

def quote_column_name(name)
  "`#{name.to_s.gsub('`', '``')}`"
end

#quote_table_name(name) ⇒ Object 



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# File 'lib/arjdbc/mysql/adapter.rb', line 240

def quote_table_name(name)
  quote_column_name(name).gsub('.', '`.`')
end

#quoted_columns_for_index(column_names, options = {}) ⇒ Object (protected) 



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# File 'lib/arjdbc/mysql/adapter.rb', line 851

def quoted_columns_for_index(column_names, options = {})
  length = options[:length] if options.is_a?(Hash)

  case length
  when Hash
    column_names.map { |name| length[name] ? "#{quote_column_name(name)}(#{length[name]})" : quote_column_name(name) }
  when Integer
    column_names.map { |name| "#{quote_column_name(name)}(#{length})" }
  else
    column_names.map { |name| quote_column_name(name) }
  end
end

#release_savepoint(name = current_savepoint_name(false)) ⇒ Object 



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# File 'lib/arjdbc/mysql/adapter.rb', line 311

def release_savepoint(name = current_savepoint_name(false))
  log("RELEASE SAVEPOINT #{name}", 'Savepoint') { super }
end

#remove_index!(table_name, index_name) ⇒ Object 



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# File 'lib/arjdbc/mysql/adapter.rb', line 542

def remove_index!(table_name, index_name)
  # missing table_name quoting in AR-2.3
  execute "DROP INDEX #{quote_column_name(index_name)} ON #{quote_table_name(table_name)}"
end

#rename_column(table_name, column_name, new_column_name) ⇒ Object 



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# File 'lib/arjdbc/mysql/adapter.rb', line 645

def rename_column(table_name, column_name, new_column_name)
  options = {}

  if column = columns(table_name).find { |c| c.name == column_name.to_s }
    type = column.type
    options[:default] = column.default if type != :text && type != :binary
    options[:null] = column.null
  else
    raise ActiveRecordError, "No such column: #{table_name}.#{column_name}"
  end

  current_type = select_one("SHOW COLUMNS FROM #{quote_table_name(table_name)} LIKE '#{column_name}'")["Type"]

  rename_column_sql = "ALTER TABLE #{quote_table_name(table_name)} CHANGE #{quote_column_name(column_name)} #{quote_column_name(new_column_name)} #{current_type}"
  add_column_options!(rename_column_sql, options)
  execute(rename_column_sql)
  rename_column_indexes(table_name, column_name, new_column_name) if respond_to?(:rename_column_indexes) # AR-4.0 SchemaStatements
end

#rename_index(table_name, old_name, new_name) ⇒ Object 



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# File 'lib/arjdbc/mysql/adapter.rb', line 548

def rename_index(table_name, old_name, new_name)
  if supports_rename_index?
    validate_index_length!(table_name, new_name) if respond_to?(:validate_index_length!)
    execute "ALTER TABLE #{quote_table_name(table_name)} RENAME INDEX #{quote_table_name(old_name)} TO #{quote_table_name(new_name)}"
  else
    super
  end
end

#rename_table(table_name, new_name) ⇒ Object 



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# File 'lib/arjdbc/mysql/adapter.rb', line 536

def rename_table(table_name, new_name)
  execute "RENAME TABLE #{quote_table_name(table_name)} TO #{quote_table_name(new_name)}"
  rename_table_indexes(table_name, new_name) if respond_to?(:rename_table_indexes) # AR-4.0 SchemaStatements
end

#rollback_to_savepoint(name = current_savepoint_name(true)) ⇒ Object 



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# File 'lib/arjdbc/mysql/adapter.rb', line 306

def rollback_to_savepoint(name = current_savepoint_name(true))
  log("ROLLBACK TO SAVEPOINT #{name}", 'Savepoint') { super }
end

#schema_creation ⇒ Object 



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# File 'lib/arjdbc/mysql/adapter.rb', line 493

def schema_creation; SchemaCreation.new self end

#show_variable(var) ⇒ Object 



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# File 'lib/arjdbc/mysql/adapter.rb', line 708

def show_variable(var)
  res = execute("show variables like '#{var}'")
  result_row = res.detect {|row| row["Variable_name"] == var }
  result_row && result_row["Value"]
end

#strict_mode? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/arjdbc/mysql/adapter.rb', line 84

def strict_mode?
  config.key?(:strict) ?
    self.class.type_cast_config_to_boolean(config[:strict]) :
      AR40 # strict_mode is default since AR 4.0
end

#structure_dump ⇒ Object

Deprecated.

no longer used - handled with (AR built-in) Rake tasks



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# File 'lib/arjdbc/mysql/adapter.rb', line 333

def structure_dump
  # NOTE: due AR (2.3-3.2) compatibility views are not included
  if supports_views?
    sql = "SHOW FULL TABLES WHERE Table_type = 'BASE TABLE'"
  else
    sql = "SHOW TABLES"
  end

  @connection.execute_query_raw(sql).map do |table|
    # e.g. { "Tables_in_arjdbc_test"=>"big_fields", "Table_type"=>"BASE TABLE" }
    table.delete('Table_type')
    table_name = table.to_a.first.last

    create_table = select_one("SHOW CREATE TABLE #{quote_table_name(table_name)}")

    "#{create_table['Create Table']};\n\n"
  end.join
end

#subquery_for(key, select) ⇒ Object

Note:

since AR 4.2

MySQL is too stupid to create a temporary table for use subquery, so we have to give it some prompting in the form of a subsubquery. Ugh!



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# File 'lib/arjdbc/mysql/adapter.rb', line 842

def subquery_for(key, select)
  subsubselect = select.clone
  subsubselect.projections = [key]

  subselect = Arel::SelectManager.new(select.engine)
  subselect.project Arel.sql(key.name)
  subselect.from subsubselect.as('__active_record_temp')
end

#supports_foreign_keys? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/arjdbc/mysql/adapter.rb', line 561

def supports_foreign_keys?; true end

#supports_index_sort_order? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/arjdbc/mysql/adapter.rb', line 255

def supports_index_sort_order?
  # Technically MySQL allows to create indexes with the sort order syntax
  # but at the moment (5.5) it doesn't yet implement them.
  true
end

#supports_indexes_in_create? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/arjdbc/mysql/adapter.rb', line 262

def supports_indexes_in_create?
  true
end

#supports_migrations? ⇒ Boolean

Returns:

  • (Boolean) 


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

def supports_migrations?
  true
end

#supports_primary_key? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/arjdbc/mysql/adapter.rb', line 250

def supports_primary_key?
  true
end

#supports_rename_index? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/arjdbc/mysql/adapter.rb', line 279

def supports_rename_index?
  return false if mariadb? || ! version[0]
  (version[0] == 5 && version[1] >= 7) || version[0] >= 6
end

#supports_savepoints? ⇒ Boolean

Returns:

  • (Boolean) 


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

def supports_savepoints?
  true
end

#supports_transaction_isolation?(level = nil) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/arjdbc/mysql/adapter.rb', line 267

def supports_transaction_isolation?
  # MySQL 4 technically support transaction isolation, but it is affected by
  # a bug where the transaction level gets persisted for the whole session:
  # http://bugs.mysql.com/bug.php?id=39170
  version[0] && version[0] >= 5
end

#supports_views? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/arjdbc/mysql/adapter.rb', line 275

def supports_views?
  version[0] && version[0] >= 5
end

#translate_exception(exception, message) ⇒ Object (protected) 



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# File 'lib/arjdbc/mysql/adapter.rb', line 865

def translate_exception(exception, message)
  return super unless exception.respond_to?(:errno)

  case exception.errno
  when 1062
    ::ActiveRecord::RecordNotUnique.new(message, exception)
  when 1452
    ::ActiveRecord::InvalidForeignKey.new(message, exception)
  else
    super
  end
end

#truncate(table_name, name = nil) ⇒ Object 



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# File 'lib/arjdbc/mysql/adapter.rb', line 522

def truncate(table_name, name = nil)
  execute "TRUNCATE TABLE #{quote_table_name(table_name)}", name
end

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

Maps logical Rails types to MySQL-specific data types.



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# File 'lib/arjdbc/mysql/adapter.rb', line 723

def type_to_sql(type, limit = nil, precision = nil, scale = nil)
  case type.to_s
  when 'binary'
    case limit
    when 0..0xfff;           "varbinary(#{limit})"
    when nil;                "blob"
    when 0x1000..0xffffffff; "blob(#{limit})"
    else raise(ActiveRecordError, "No binary type has character length #{limit}")
    end
  when 'integer'
    case limit
    when 1; 'tinyint'
    when 2; 'smallint'
    when 3; 'mediumint'
    when nil, 4, 11; 'int(11)'  # compatibility with MySQL default
    when 5..8; 'bigint'
    else raise(ActiveRecordError, "No integer type has byte size #{limit}")
    end
  when 'text'
    case limit
    when 0..0xff;               'tinytext'
    when nil, 0x100..0xffff;    'text'
    when 0x10000..0xffffff;     'mediumtext'
    when 0x1000000..0xffffffff; 'longtext'
    else raise(ActiveRecordError, "No text type has character length #{limit}")
    end
  when 'datetime'
    return super unless precision

    case precision
      when 0..6; "datetime(#{precision})"
      else raise(ActiveRecordError, "No datetime type has precision of #{precision}. The allowed range of precision is from 0 to 6.")
    end
  else
    super
  end
end

#update_sql(sql, name = nil) ⇒ Object 



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

def update_sql(sql, name = nil)
  super
end

#valid_type?(type) ⇒ Boolean

Note:

since AR 4.2

Returns:

  • (Boolean) 


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# File 'lib/arjdbc/mysql/adapter.rb', line 767

def valid_type?(type)
  ! native_database_types[type].nil?
end